Why are the constellations in the summer sky different from those in the winter?

Awoman stands a distance d from a loud motor that emits sound uniformly in all directions. the sound intensity at her position is an uncomfortable 2.0×10-3 w/m2. at a distance 2.6 times as far from the motor, what are (a) the sound intensity and (b) the sound intensity level relative to the threshold of hearing?

We put a force of 50n on an object and the acceleration is 100 m/s². what is the mass of the object?

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?