please help and explain 4.Most significant astronomical discovery of the 1700s: A. Ceres B. Moons of Jupiter C. Rings of

[answerhappygod]

please help and explain
4.Most significant astronomical discovery of the 1700s:
A. Ceres
B. Moons of Jupiter
C. Rings of Saturn
D. UranusE. Neptune
5.Was classified as a planet. Now classified as a dwarf planet.
A. Ceres
B. Pluto
C. Eris
D. A & B
E. A & B & C
6. Landed on Mars using a jet-powered sky crane:
A. Viking 1 and 2
B. Pathfinder/Sojourner
C. Spirit
D. Opportunity
E. Curiosity
7. The semi-major axis of a planet's moon is 0.061 Earth-moon distances. Its orbital period is 0.046 Earth lunar months. What is the planet's mass?
A. 0.026 Earth masses B. 0.11 Earth masses C. 9.3 Earth masses D. 38 Earth masses
8. ？After an earthquake, not detected on the opposite side of Earth due to its liquid outer core:
A. P waves
B. Q waves
C. R waves
D. S waves
E. T waves
9. ？ Greenhouse gas most responsible for Earth's increasing surface temperature:
A. Carbon dioxide
B. Chlorofluorocarbons (CFCs)
C. Methane
D. Nitrous oxide
E. Water vapor
Which NASA spacecraft would you use to image a dusty cloud of gas?
A. Spitzer
B. Hubble
C. Chandra
D. Fermi