Superman lived on another planet where the acceleration due to gravity is 23.6 m/s^2. if a woman falls from a building that is 65m tall, how long he have to save her before she hits the ground

Light from the sun reaches the earth in 8.3 minutes. the velocity is 3.00 x 10^8 m/s. how far is earth from the sun? i know how to get to d = (3 x 10^8 m/s)(498 sec). i just don't know how to get from there to the answer being 1.5 x 10^11 m.

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?

Apiece of metal 75g at 110°c is dropped in a container with 500g at 20°c. the h2o if temperature is 24°c find specific heat capacity of metal