a. 2,093.33 [tex] in^{3} [/tex]
b. 20 cups
c. 27 cups
To find the volume of a hemisphere, we must use the formula: 2/3[tex] \pi [/tex][tex] r^{3} [/tex] . Then, to determine how many cups he needs to scoop the water out, we have to find the volume of water that each cup can hold, and divide by the total volume the sink can hold. These processes are shown in the attached image.