I will help you by telling you how to solve them. I will show you one of the ways to solve this.
The first way you can solve this is by multiplying and then reducing the fraction. To do this all you need to do is multiply the numerators together and then you multiply the denominators together, after you do this you simply reduce the fraction to it's lowest possible numerator and denominator. For example:
The kinetic energy of an object is given by: Kinetic energy = 1/2 * mass * velocity If the kinetic energy of the pendulum at the top of its swing is 0, then this tells us that the velocity of the pendulum at that point is 0