(a) Write a Matlab command to produce matrix A where A(1,1) = 10, A(2,1) = 8, A(1,2) = 5, and A(2,2) = 20.

(b) Given row vector e = [4,5,6,9]. Write a Matlab command to calculate the square root of each element of e, and store the results in row vector b.

(c) E is a 10 by 5 matrix. Write a Matlab command to add all elements of E in row number 10, and store the result in variable total.

(d) B = [4,5,6; 2,0,4; 7,8,9; 3,2,1]. Write a Matlab command to add elements in row 1 and row 2 of matrix B on element-by-element basis, and store the results in row vector b.

## Please just write the codes down no need for Extra explanation details.