An astronaut is floating happily outside her spaceship, which is orbiting the earth at a distance above the earth’s surface equal to 1 earth radius. the astronaut’s weight is

Zero

Explanation:

An astronaut floating happily outside her spaceship simply means she is experiencing weightlessness because the earth's gravity no longer has influence on her and hence no gravitational pull. At this state her weight is zero. This can further be explained by the following illustration:

The astronaut mass is constant but the gravity is zero i.e

mass = constant

g (acceleration due to gravity) = 0

Weight =?

Weight = Mass x Acceleration due to gravity

W = M x g

W = M x 0

W = 0

Since her weight is zero, hence she will begin to float.

the independent variable, or the one that is intentionally manipulated is the speed.

thermal energy is the answer