Compute the requested values given the following information.

${\displaystyle \underset{-2}{\overset{2}{}}}f(x)dx=A,{\displaystyle \underset{2}{\overset{-6}{}}}f(x)dx=B,{\displaystyle \underset{-6}{\overset{-2}{}}}g(x)dx=C,{\displaystyle \underset{-2}{\overset{2}{}}}g(x)dx=D$

$1$a$)$ Find the following value in terms of $A,B,C$ and $D.$

${\displaystyle \underset{-6}{\overset{2}{}}}f(x)+g(x)dx$

$1$b$)$ Find the following value in terms of $A,B,C$ and $D.$

${\displaystyle \underset{-6}{\overset{-2}{}}}2f(x)-3g(x)dx$