For what values of c does the binomial 5-3c take on a value which is greater than 80?

Asocial networking site currently has 400,000 active members, and that figure is predicted to increase by 32% each year. the following expression represents the number of active members on the site after t years.

The graph of g(x) is a translation of y = which equation represents g(x)?

Find the cosine function that is represented in the graph.