If a star is 75 light years away, how long is it before we see the light from that star on earth ?

Aray diagram for a refracted light day is shown. what does the dashed line represent

In raising a 6200-n piano with a pulley system, the movers note that, for every 2.2 m of rope pulled down, the piano rises 0.12 m . ideally, find the force required to lift the piano.

The graph describes the motion of an object. the object moves with from a to b. it from b to c. it moves with from c to d.