Solve using the compound interest formula $FV=PV(1+i{)}^n.$

a$.$ Find $FV,$ when $PV=$$$2,566\mathrm{.}00,i=0\mathrm{.}04,n=\frac{19}{12}$

Round to two decimal places

b$.$ Find $PV,$ when $FV=$$$4,428\mathrm{.}12,i=0\mathrm{.}00375,n=42$

Round to two decimal places