The top question is already filled out (if you see an error in the top one can you let me know in the comments only please?) and what I need to answer is the bottom question, can any of you help me, please?

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b

add an image

step-by-step explanation:

its 60

4 x 12 = 48

3 x 4 = 12

48 + 12 = 60

yeeeet