Coasting due west on your bicycle at 8 m/s, you encounter a sandy patch of road 7.2m across. When you leave the sandy patch your speed has been reduced to 6.5 m/s. Assuming
the bicycle slows with constant acceleration, what was its acceleration in the sandy patch?
Give your answer in m/s2 and round to the nearest tenth. (0.0)

V = (v1 + v2) / 2 = (8 + 6.5) / 2 = 7.25 m/s     average speed

t = 7.2 / 7.25 = .993 sec      time to cross patch

a = (v2 - v1) / t = (6.5 - 8) / .993 = -1.51 m/s^2     or 1.5 m/s^2

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.