yes, they are all proportional
ONP=43 degrees
LNO=137 degrees
MNP=137 degrees
A straight line equals 180 degrees, so the angles need to add up to that amount. Hope this helps!
Place values:
As each is in a different place value, when we add them neither will affect the other, meaning:

Answer: B 4.39
True because it says the sum of 2 trinomials that my answer. hope I helped.