I. Simplify the following Boolean functions using K-maps.
6. F(A, B, C, D) = ?(0,2,3,5,7,8,10,11,14,15)
7. F(A, B, C, D) = ?(1,3,5,7,13,15)
8. F(A, B, C, D) = ?(1,3,6,9,11,12,14)
9. F(A, B, C, D) = \overline{A}\overline{B}C\overline{D} + \overline{A}B\overline{C}D + A\overline{B}C\overline{D} + A\overline{B}C\overline{D} + A\overline{B}C\overline{D}
don'tcares are at (0,2,9,12)