$3.$ Correct the divide$-$by$-$zero errors as follows:

a$.$ Evaluate the formula in cell B$17$ to determine which cell is causing the divide$-$by$-$zero error.

b$.$ Correct the formula in cell B$17,$ which should divide the income per program $($cell B$15)$ by the minimum number of trainees $($cell B$5).$

c$.$ Fill the range C$17$:F$17$ with the formula in cell B$17.($Hint: You will correct the new error in cell C$17$ in the following steps.$)$