What fraction of a dozen is a score

The graph shows the distance y, in inches, a pendulum moves to the right (positive displacement) and to the left (negative displacement), for a given number of seconds x. how many seconds are required for the pendulum to move from its resting position and return? enter your answer in the box.

Another type of subtraction equation is 16-b=7. explain how you would sole this equation then solve it.

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie