If the telephone was invented in 1876 how old was it in 1991 how long had it been around

The graph shown below expresses a radical function that can be written in the form f(x)=a(x+k)1/n+c what does the graph tell you about the value of n in this function

Consider the graph of the exponential function y=3(2)×

If x is 6, then 7x= a. 13 b. 42 c. 42x d. 76