Answer
a). 4
b). 6
c). subtracted
Work Step by Step
a).
$\frac{b^{7}}{b^{3}}$ = $\frac{b.b.b.b.b.b.b}{b.b.b}$ = $b^{7-3}$ = $b^{4}$
b).
$\frac{b^{8}}{b^{2}}$ = $\frac{b.b.b.b.b.b.b.b}{b.b}$ = $b^{8-2}$ = $b^{6}$
c).
When dividing exponential expressions with the same base the exponents will be subtracted.