What is the net force when a pair of balanced forces acts on an object

What is meant by the statement" the melting poin of glycerine is 13 degree celsius

The earth exerts a gravitational force of 500 n on amy. what is amy’s mass in kg?

Me pl give an example of a collision in real life. use the law of conservation of energy to describe the transfer of momentum. be sure and discuss the momentum before and after the collision occurs. you will need at least 3 sentences to thoroughly answer this question.