4. Minimize the following Boolean functions into product-of-sums form using a K-map (а) F(a, b, c, d) — Z(1,4, 5, 7, 10, 11) (b) F(a,b, c, d) = II(1, 2, 6, 8, 10, 12, 14, 15)

Fig: 1

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