Assuming t is a time unit.
The initial amount is when t = 0, so it is 9.8 * 1 = 9.8. The growth rate is how much the amount goes up by for every increase of 1 in t. This is 1.35 because that is the part being affected by t. we plug in 0 for t to get 9.8 as the initial amount. The growth rate is just 135% factor, or 35% more each time, because 1.35 is the base of the exponent.