A $50-$kCi $137$Cs source is stored under water with storage facility dimensions of $50$ ft by $50$ ft by $50$ ft$.$ At a distance of $1$ ft from the source, use the Taylor form of the buildup factor to find:

$($a$)$ the total $($collided $+$ uncollided$)$ absorbed dose rate in water, in mGy h$-1$; and

$($b$)$ the total $($collided $+$ uncollided$)$ exposure rate, in mR h$-1.$