Horizons - Exploring the Universe 11th edition

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Michael A. Seeds and Dana Backman
Publisher: Cengage Learning

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  • Chapter 1: Here and Now
    • 1: Active Figures
    • 1: General Problem (4)
    • 1: End of Chapter Problem (10)
    • 1: Review Exercise (14)
    • 1: End of Chapter Review Question (10)
    • 1: Ranking Task Exercise (2)

  • Chapter 2: The Sky
    • 2: Active Figures (4)
    • 2: General Problem (5)
    • 2: End of Chapter Problem (11)
    • 2: Review Exercise (17)
    • 2: End of Chapter Review Question (9)
    • 2: Ranking Task Exercise (1)

  • Chapter 3: Cycles of the Sky
    • 3: Active Figures (5)
    • 3: General Problem (7)
    • 3: End of Chapter Problem (12)
    • 3: Review Exercise (28)
    • 3: End of Chapter Review Question (15)
    • 3: Ranking Task Exercise (3)

  • Chapter 4: The Origin of Modern Astronomy
    • 4: Active Figures (7)
    • 4: General Problem (8)
    • 4: End of Chapter Problem (16)
    • 4: Review Exercise (39)
    • 4: End of Chapter Review Question (22)
    • 4: Ranking Task Exercise (2)

  • Chapter 5: Light and Telescopes
    • 5: Active Figures (2)
    • 5: General Problem (5)
    • 5: End of Chapter Problem (10)
    • 5: Review Exercise (24)
    • 5: End of Chapter Review Question (17)
    • 5: Ranking Task Exercise (2)

  • Chapter 6: Atoms and Starlight
    • 6: Active Figures (3)
    • 6: General Problem (4)
    • 6: End of Chapter Problem (10)
    • 6: Review Exercise (24)
    • 6: End of Chapter Review Question (15)
    • 6: Ranking Task Exercise (2)

  • Chapter 7: The Sun
    • 7: Active Figures (2)
    • 7: General Problem (3)
    • 7: End of Chapter Problem (1)
    • 7: Review Exercise (24)
    • 7: End of Chapter Review Question (17)
    • 7: Ranking Task Exercise (2)

  • Chapter 8: The Family of Stars
    • 8: Active Figures (2)
    • 8: General Problem (5)
    • 8: End of Chapter Problem (13)
    • 8: Review Exercise (21)
    • 8: End of Chapter Review Question (16)
    • 8: Ranking Task Exercise (3)

  • Chapter 9: The Formation and Structure of Stars
    • 9: Active Figures (7)
    • 9: General Problem (5)
    • 9: End of Chapter Problem (6)
    • 9: Review Exercise (36)
    • 9: End of Chapter Review Question (22)
    • 9: Ranking Task Exercise (2)

  • Chapter 10: The Deaths of Stars
    • 10: Active Figures (5)
    • 10: General Problem (5)
    • 10: End of Chapter Problem (15)
    • 10: Review Exercise (34)
    • 10: End of Chapter Review Question (24)
    • 10: Ranking Task Exercise (4)

  • Chapter 11: Neutron Stars and Black Holes
    • 11: Active Figures (4)
    • 11: General Problem (3)
    • 11: End of Chapter Problem (8)
    • 11: Review Exercise (24)
    • 11: End of Chapter Review Question (19)
    • 11: Ranking Task Exercise (2)

  • Chapter 12: The Milky Way Galaxy
    • 12: Active Figures (2)
    • 12: General Problem (4)
    • 12: End of Chapter Problem (12)
    • 12: Review Exercise (24)
    • 12: End of Chapter Review Question (16)
    • 12: Ranking Task Exercise (2)

  • Chapter 13: Galaxies
    • 13: Active Figures (2)
    • 13: General Problem (3)
    • 13: End of Chapter Problem (9)
    • 13: Review Exercise (21)
    • 13: End of Chapter Review Question (14)
    • 13: Ranking Task Exercise (2)

  • Chapter 14: Active Galaxies and Supermassive Black Holes
    • 14: Active Figures (2)
    • 14: General Problem (2)
    • 14: End of Chapter Problem (10)
    • 14: Review Exercise (23)
    • 14: End of Chapter Review Question (16)
    • 14: Ranking Task Exercise (2)

  • Chapter 15: Modern Cosmology
    • 15: Active Figures (5)
    • 15: General Problem (3)
    • 15: End of Chapter Problem (8)
    • 15: Review Exercise (25)
    • 15: End of Chapter Review Question (13)
    • 15: Ranking Task Exercise (2)

  • Chapter 16: The Origin of the Solar System
    • 16: Active Figures (4)
    • 16: General Problem (4)
    • 16: End of Chapter Problem (9)
    • 16: Review Exercise (25)
    • 16: End of Chapter Review Question (20)
    • 16: Ranking Task Exercise (3)

  • Chapter 17: The Terrestrial Planets
    • 17: Active Figures (4)
    • 17: General Problem (6)
    • 17: End of Chapter Problem (14)
    • 17: Review Exercise (61)
    • 17: End of Chapter Review Question (39)
    • 17: Ranking Task Exercise (6)

  • Chapter 18: The Jovian Planets, Pluto, and the Kuiper Belt
    • 18: Active Figures (6)
    • 18: General Problem (7)
    • 18: End of Chapter Problem (3)
    • 18: Review Exercise (43)
    • 18: End of Chapter Review Question (28)
    • 18: Ranking Task Exercise (4)

  • Chapter 19: Meteorites, Asteroids and Comets
    • 19: Active Figures (4)
    • 19: General Problem (4)
    • 19: End of Chapter Problem (12)
    • 19: Review Exercise (25)
    • 19: End of Chapter Review Question (15)
    • 19: Ranking Task Exercise (2)

  • Chapter 20: Life on Other Worlds
    • 20: Active Figures (3)
    • 20: General Problem (3)
    • 20: End of Chapter Problem (8)
    • 20: Review Exercise (25)
    • 20: End of Chapter Review Question (15)
    • 20: Ranking Task Exercise (2)

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  1. Active Figures - visualize astronomy in action
    Animated figures from the text come to life and allow students to visualize phenomena and processes that can't be represented on the printed page. In addition to viewing animations of the figures from the text, students can change variables to see the effects, conduct suggested explorations of the principles involved in the figure, and take and receive feedback on quizzes related to the figure.

  2. Reading Questions - test your students' reading comprehension
    Reading questions test for comprehension of the text material. You can assign these questions as incentive to keep up on the reading assignments.

  3. Guidepost Questions - get organized right from the start
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  4. Review Questions - end-of-chapter test of understanding
    After reading the chapter and participating in class discussions, end-of-chapter review questions help pull all of it together one final time.

  5. Ranking Tasks - understanding how scientists know
    Ranking questions are designed to help your students understand why scientist can make logical arguments about how nature works.

  6. Seeds eBook Version - immediate access to the textbook: anywhere, anytime
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Question Group Key
AF - Active Figures
GP - General Problems
P - End of Chapter Problem
RE - Review Exercise
RQ - End of Chapter Review Question
RTE - Ranking Task Exercise


Question Availability Color Key
BLACK questions are available now
GRAY questions are under development


Group Quantity Questions
Chapter 1: Here and Now
1.GP 4 XP.001 XP.002 XP.003 XP.004
1.LL 2 001 003
1.P 10 001 002 003 004 005 006 007 008 009 010
1.RE 14 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014
1.RQ 8 XP.001 001 002 003 004 005 006 007
1.RTE 2 001 002
Chapter 2: The Sky
2.AF 4 001 002 003 004
2.GP 5 XP.001 XP.002 XP.003 000.01A 000.01B
2.LL 1 002
2.P 11 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 001 01a 002 003 03b 004 07
2.RE 17 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017
2.RQ 8 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 001 005
2.RTE 1 001
Chapter 3: Cycles of the Sky
3.AF 5 001 002 003 004 005
3.GP 7 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007
3.LL 1 001
3.P 12 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 002 003 004 007 008
3.RE 28 XP.001 XP.002 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025 XP.026 XP.027 XP.028 XP.029 XP.030 XP.031 XP.032
3.RQ 14 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 002 004 005 007
3.RTE 3 001 002 003
Chapter 4: The Origin of Modern Astronomy
4.AF 7 001 002 003 004 005 006 007
4.GP 8 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008
4.LL 3 001 002 003
4.P 16 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 001 002 003 004 005 006 009
4.RE 39 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025 XP.026 XP.027 XP.028 XP.029 XP.030 XP.031 XP.032 XP.033 XP.034 XP.035 XP.036 XP.037 XP.038 XP.039
4.RQ 19 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 008 010 011 012 013
4.RTE 2 001 002
Chapter 5: Light and Telescopes
5.AF 2 001 002
5.GP 5 XP.001 XP.002 XP.003 XP.004 XP.005
5.LL 2 001 003
5.P 10 001 002 003 004 005 006 007 008 009 010
5.RE 24 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024
5.RQ 15 XP.001 001 002 003 004 005 006 007 008 009 010 012 013 014 015
5.RTE 2 001 002
Chapter 6: Atoms and Starlight
6.AF 3 001 002 003
6.GP 4 XP.001 XP.002 XP.003 XP.004
6.LL 2 003 004
6.P 10 001 002 003 004 005 006 007 008 009 010
6.RE 24 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024
6.RQ 13 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 010 011 013
6.RTE 2 001 002
Chapter 7: The Sun
7.AF 2 001 002
7.GP 3 XP.001 XP.002 XP.003
7.LL 2 002 003
7.P 1 011
7.RE 24 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024
7.RQ 15 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015
7.RTE 2 001 002
Chapter 8: The Family of Stars
8.AF 2 001 002
8.GP 5 XP.001 XP.002 XP.003 XP.004 XP.005
8.LL 1 002
8.P 13 XP.001 XP.004 XP.005 001 003 004 006 008 009 010 011 012 013
8.RE 21 XP.001 XP.002 XP.003 XP.004 XP.006 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.025
8.RQ 15 XP.001 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 001 002 003 004 008 012 013
8.RTE 3 001 002 003
Chapter 9: The Formation and Structure of Stars
9.AF 7 001 002 003 004 005 006 007
9.GP 5 XP.001 XP.002 XP.003 XP.004 XP.005
9.LL 2 001 004
9.P 6 XP.001 XP.002 002 003 007 009
9.RE 36 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025 XP.026 XP.027 XP.028 XP.029 XP.030 XP.031 XP.032 XP.033 XP.034 XP.035 XP.036
9.RQ 20 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 001 002 004 005 008 010 012
9.RTE 2 001 002
Chapter 10: The Deaths of Stars
10.AF 5 001 002 003 004 005
10.GP 5 XP.001 XP.002 XP.003 XP.004 XP.005
10.LL 2 002 003
10.P 15 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 002 003 003.alt 004 005 006 007 009 010
10.RE 34 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025 XP.026 XP.027 XP.028 XP.029 XP.030 XP.031 XP.032 XP.033 XP.034
10.RQ 22 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 003 005 006 007 014
10.RTE 4 001 002 003 004
Chapter 11: Neutron Stars and Black Holes
11.AF 4 001 002 003 004
11.GP 3 XP.001 XP.002 XP.003
11.LL 2 001 002
11.P 8 XP.001 XP.002 XP.003 001 002 003 005 006 007
11.RE 24 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024
11.RQ 17 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 002 003 006 010 012 013 014 015 016
11.RTE 2 001 002
Chapter 12: The Milky Way Galaxy
12.AF 2 001 002
12.GP 4 XP.001 XP.002 XP.003 XP.004
12.LL 2 001 002
12.P 12 XP.001 XP.002 XP.003 001 002 003 004 005 006 007 009 010
12.RE 24 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024
12.RQ 14 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 003 004 005 007 011 012 013
12.RTE 2 001 002
Chapter 13: Galaxies
13.AF 2 001 002
13.GP 3 XP.001 XP.002 XP.003
13.LL 2 003 004
13.P 9 001 002 003 004 005 006 007 008 009
13.RE 21 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021
13.RQ 12 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 003 009 011
13.RTE 2 001 002
Chapter 14: Active Galaxies and Supermassive Black Holes
14.AF 2 001 002
14.GP 2 XP.001 XP.002
14.LL 3 001 002 003
14.P 10 XP.001 001 002 003 004 005 006 007 008 009
14.RE 23 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023
14.RQ 13 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 003
14.RTE 2 001 002
Chapter 15: Modern Cosmology
15.AF 5 001 002 003 005 006
15.GP 3 XP.001 XP.002 XP.003
15.LL 1 001
15.P 8 XP.001 001 002 003 004 005 006 007
15.RE 25 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025
15.RQ 12 XP.001 XP.002 XP.003 001 003 004 005 007 008 009 011 012
15.RTE 2 001 002
Chapter 16: The Origin of the Solar System
16.AF 4 001 002 003 004
16.GP 4 XP.001 XP.002 XP.003 XP.004
16.LL 2 001 002
16.P 9 001 002 003 004 005 006 007 008 009
16.RE 25 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025
16.RQ 18 XP.001 XP.002 XP.003 001 002 003 004 005 006 007 008 009 010 011 012 013 014 016
16.RTE 3 001 002 003
Chapter 17: The Terrestrial Planets
17.AF 4 001 002 003 004
17.GP 6 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006
17.LL 2 002 003
17.P 14 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 001 003 004 005 006
17.RE 61 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025 XP.026 XP.027 XP.028 XP.029 XP.030 XP.031 XP.032 XP.033 XP.034 XP.035 XP.036 XP.037 XP.038 XP.039 XP.040 XP.041 XP.042 XP.043 XP.044 XP.045 XP.046 XP.047 XP.048 XP.049 XP.050 XP.051 XP.052 XP.053 XP.054 XP.055 XP.056 XP.057 XP.058 XP.059 XP.060 XP.061
17.RQ 37 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025 XP.026 XP.027 XP.028 XP.029 XP.030 XP.031 XP.032 XP.033 XP.034 001 010 013
17.RTE 6 001 002 003 004 005 006
Chapter 18: The Jovian Planets, Pluto, and the Kuiper Belt
18.AF 6 001 002 003 004 005 006 07
18.GP 7 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007
18.LL 3 001 002 003
18.P 3 001 002 004
18.RE 43 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025 XP.026 XP.027 XP.028 XP.029 XP.030 XP.031 XP.032 XP.033 XP.034 XP.035 XP.036 XP.037 XP.038 XP.039 XP.040 XP.041 XP.042 XP.043
18.RQ 25 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 004 005 012 013
18.RTE 4 001 002 003 004
Chapter 19: Meteorites, Asteroids and Comets
19.AF 4 001 002 003 004
19.GP 4 XP.001 XP.002 XP.003 XP.004
19.LL 3 001 002 003
19.P 12 XP.001 XP.002 XP.003 001 002 003 004 005 006 007 008 009
19.RE 25 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025
19.RQ 12 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 012 015
19.RTE 2 001 002
Chapter 20: Life on Other Worlds
20.AF 3 001 002 003
20.GP 3 XP.001 XP.002 XP.003
20.LL 2 001 002
20.P 8 001 002 003 004 005 006 007 008
20.RE 25 XP.001 XP.002 XP.003 XP.004 XP.005 XP.006 XP.007 XP.008 XP.009 XP.010 XP.011 XP.012 XP.013 XP.014 XP.015 XP.016 XP.017 XP.018 XP.019 XP.020 XP.021 XP.022 XP.023 XP.024 XP.025
20.RQ 13 001 002 003 004 005 006 007 008 009 010 011 012 013
20.RTE 2 001 002
Total 1329 (4)