(a) Let $B=4250(1.05)^t$ give the balance of a bank account after $t$ years. If the formula for $B$ is written $B=4250 e^{kt}$, estimate the value of $k$ correct to four decimal places.
$k \approx$

(b) The balance of a bank account after $t$ years is given by the formula $B= 8250 e^{0.08 t}$. If the formula for $B$ is written $B= 8250 b^t$, find $b$ exactly, and give the value of $b$ correct to four decimal places.
$b =$
$b \approx$ (to 4 decimal places)