You are grading for a future building pad and placing sandy fill material. The optimum moisture content of this material is $17\%.$ The in$-$situ moisture content of the sandy material is $9\%.$ The fill material will be placed at a rate of $275CC\frac{Y}{h}r.$ The specified dry weight of the compacted earth is $2,750lb\frac{s}{c}y.$

a$.$ How many gallons of water must be supplied each hour to increase the moisture content of the earth from $9\%$ to $17\%?$ The weight of water is $8\mathrm{.}33lbs\frac{.}{g}al.(5$ points$)$

b$.($Hint: you need to calculate the number of gallons needed to compact $275$ CY since the question asks for how many gallons are needed per hour.$)$