Set up the equation as follows:

150x represents the dog's speed, 100x represents the squirrel's speed, and 200 represents the distance the squirrel has on the dog. x is the amount of minutes that elapse.
Subtract 100x from both sides.

Divide both sides by 50.

It will take the dog 4 minutes to catch up with the squirrel.
C (third graph, the parabola); To find if it is a function or not draw a vertical line on the graph. If the vertical line could never intercept the figure more than once anywhere on the graph then it is a function.
When someone lends money to someone else, the borrower usually pays a fee to the lender. This fee is called 'interest'. 'Simple' interest, or 'flat rate' interest. The amount of simple interest paid each year is a fixed percentage of the amount borrowed or lent at the start. <span>Interest = Principal × Rate × Time</span>