Which could be the first step and simplifying this expression? Check all that apply.

Hi, can anyone show me how to do this problem? 100 points for this. in advance

Identify the initial amount a and the growth factor b in the exponential function. a(x)=680*4.3^x

Study results indicate that the mean length of time people spend on a bus in a city is between 21.2 min and 24.5 min what is the study margin of the error?