Can you tell me if these are correct? I am not sure that I understand this.

Question

1. Which is the solution for the determinant?
|10 0)|
5 -7
Answer- -70?

2.Which is the solution for the determinant?
|1 7)|
0 -3
Answer- -3

Answer 1

Did I answer these correct?

19.Given matrices A, B, and C are all 2x2, determine whether the equation is true for the given matrices.
C(A+B)= CA + CB
Answer- False

20.Matrix multiplication is not commutative.
Answer-False

21.For matrices, A + B = B + A
Answer-True