Assume that there were 1 million bacteria on an apple at noon on Monday and that a bacterium doubles every hour on average. Let f(t)=M represent the number of bacteria(in millions) on an apple at t hours since noon on Monday. An equation for f is f(t)=2^t.

1. Explain why f^-1(M)=log2(M)

2. Find log2(8). What does your result mean in terms of the bacterium?