A = {5, 6, 7}

We have to find P(A) which is power set of A

The power set of set A is collection of all possible subsets of A

The possible subsets of A are {ϕ}, {5}, {6}, {7}, {5,6}, {5,7}, {6, 7}, {5, 6, 7}

Hence the power set P(A) will be

P(A) = {{ϕ}, {5}, {6}, {7}, {5,6}, {5,7}, {6, 7}, {5, 6, 7}}