Evaluate the following integrals.

$($a$){\displaystyle \underset{0}{\overset{4}{}}}{x}^{3}dx$

$($b$){\displaystyle \underset{0}{\overset{1}{}}}{e}^{x}dx$

$($c$){\displaystyle \underset{6}{\overset{10}{}}}5-x^{2}dx$