Implement the function $F(A,B,C)={\displaystyle \underset{?}{\overset{?}{}}}(1,3,5,6)$ using SOP.

Implement the function $F(A,B,C,D)={\displaystyle \underset{?}{\overset{?}{}}}(5,8,10,11,13)+d(7,12,14)$ using SOP.

Implement the function $F(A,B,C,D)=$prod$(2,4,5,8)*D(10,11,12,13,14,15)$ using POS.

Implement the logic function with $5$ inputs that outputs a $1$ when exactly two of the inputs are $1.$ Note anything interesting about your result.