What is another expression that is equal to 3(n+6)

(a)3n+6

(b)3n+18

(c)2n+2+n+4

(d)4(n++6)

(e)4(n+-6)

Calculate the average rate of change over the interval [1, 3] for the following function. f(x)=4(5)^x a. -260 b. 260 c. 240 d. -240