First problem (number 9):
KBM is 30º and KBT is 90º. Together that is 120º.
Subtract 120º from 180º to get the measure of MBE: 60º.
MBE is the same as NBT, so that means 180 - 60 is EBN.
EBN is 60º. The answer is B.
Second problem (number 10):
We're going to use the same process as before. 50 plus 90 is 140.
180 minus 140 is 40.
HLA is the same as ELR.
ELR is 40, and 180 - 40 = 140.
ALR is 140º. The answer is A.
Hope this helps!