Please need answers with worked solutions asap!!

Keneila is attempting to ski down a 20 m high friction free hill for the first time. she has a speed 10 m/s at the top. what is her kinetic energy when she is a the bottom, 20 m ? (a)2500 j (b)9800 j (c)12300 j (d)3100j (e)15000j

What type of nuclear decay causes the atomic number of an element to increase by 1?

An object has a weight of 500 on earth what is the mass of this object