EXAMPLE $4-35$

Use a Karnaugh map to minimize the following POS expression:

$(B+C+D)(A+B\frac{+}{b}ar(C)+D)(\frac{?}{\text{b}\text{a}\text{r}}(A)+B+C\frac{+}{b}ar(D))(A\frac{+}{b}ar(B)+C+D)(\frac{?}{\text{b}\text{a}\text{r}}(A)\frac{+}{b}ar(B)+C+D)$