Consider two functions $f$ and $g$ on $1,8$ such that ${\displaystyle \underset{1}{\overset{\phantom{}}{}}}f(x)dx=13,{\displaystyle \underset{1}{\overset{\phantom{}}{}}}g(x)dx=6,{\displaystyle \underset{5}{\overset{0}{}}}f(x)dx=5,$ and ${\displaystyle \underset{1}{\overset{5}{}}}g(x)dx=2.$ Evaluate the following integrals.

a$.{\displaystyle \underset{1}{\overset{5}{}}}7f(x)dx=56($Simplify your answer.$)$

b$.{\displaystyle \underset{1}{\overset{8}{}}}(f(x)-g(x))dx=7($Simplify your answer.$)$

c$.{\displaystyle \underset{1}{\overset{5}{}}}(f(x)-g(x))dx=6($Simplify your answer.$)$

d$.{\displaystyle \underset{5}{\overset{8}{}}}(g(x)-f(x))dx=-1($Simplify your answer.$)$

e$.{\displaystyle \underset{5}{\overset{8}{}}}9g(x)dx=,($Simplify your answer.$)$