A trigonometric function (sine cosine) has form
where are real numbers.
The coefficient is called the amplitude. It is half the distance between the highest point on the wave and the lowest point point on the wave. The coefficient is called the frequency. It shows the number of times the wave goes though complete cycles. The period is the number of radians which gives the full cycle it is determined by .
Next, the coffiecient is called the phase shift, it shifts the wave to the left or right by that many radians. If the wave is shifted to the left, if the wave is shifted to the right.
Finally, just determines the shift up or down for the wave. If the wave is moved up by that many units. If the wave is moved down by that many units. And if the wave is just left the way it is.
Now you should be able to do your problems, if not say where you need help with.