cannot. leave in mm lah, plus, your answer some use not enough
sf, not 58.5 degree but is 58.0 degrees. degrees in 1 dp, not
3sf
If they want it specifically in mm, they will say "leave your
answers in mm" but they only stated "correct to nearest mm".
I just checked again, my answer is 58.5 degrees because I used
sin BCA = 550/645, prolly you guys used another method.
As for the sets, I never said anything about null
A { 1, 4, 9, 16}
B { 3, 6, 9, 12, 15}
A compliment { 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15 }
A compliment intersect B =
3, 6, 12, 15