Simplify the following functions using k$-$map.

a$)F(x,y,z)={\displaystyle \underset{?}{\overset{?}{}}}(0,2,4,5,6)$

b$)F(x,y,z,w)={\displaystyle \underset{?}{\overset{?}{}}}(11,12,13,14,15)$

c$)F=A^{\text{'}}{B}^{\text{'}}{C}^{\text{'}}{D}^{\text{'}}+B{C}^{\text{'}}D+A^{\text{'}}{C}^{\text{'}}D+A^{\text{'}}BCD+AC{D}^{\text{'}}$