yes.
this is division. 36 divided by 12 is 3. 63 divided by 21 is 3.
About 145 I gonna guess I dont know if that's right
Rotation counterclockwise 90 degrees has the rule
(x,y) -> (-y,x)
So the image is obtained, according to the rule,
(2,3) -> (-3,2)
Answer: she will need 4 yards of fabric to make 2 shirts