Evaluate the integrals for $f(x)$ shown in the figure below. The two parts of the graph are semicircles.

a$){\displaystyle \underset{0}{\overset{2}{}}}4f(x)dx=($i$)$

b$){\displaystyle \underset{0}{\overset{6}{}}}2f(x)dx=-$

c$){\displaystyle \underset{1}{\overset{4}{}}}3f(x)dx=-$

d$){\displaystyle \underset{1}{\overset{6}{}}}|2f(x)|dx=($i$)$