An airplane flies at 40 m/s at an altitude of 500 m. The pilot drops a package that falls to the ground, How long does it take for the package to reach the ground?

10.1 s

Explanation:

The time of flight of the package is entirely determined by its vertical motion, which is a free fall motion (it is acted upon the force of gravity only). Therefore, it is a uniformly accelerated motion, so we can use the suvat equation:

where

s is the vertical distance covered

u is the initial vertical velocity

t is the time of flight

is the acceleration due to gravity

For the package in this problem, we have:

s = 500 m is the vertical distance covered

u = 0 is the initial vertical velocity (initially it has only horizontal motion)

So, solving for t, we find the time of flight:

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.