Samuel took an antique clock that his grandfather had purchased, to be appraised. the appraiser evaluated the current price of the clock to be $400 and stated that the value will continue to increase at 2% per year.

which of the following graphs shows the value of the antique clock, y, in dollars, after x years?

This is an exponential growth problem. Exponential growth can be expressed mathematically in the following way: 
.
Parameter a presents initial amount.
Parameter r is percentage increase. 
Parameter t is time.
An equation that would describe given problem is:

t is the time in years.
I attached the graph of this function.