Answer:
m<B = 141 degrees
Explanation:
This shape is a heptagon meaning its angles should have a sum of 900 degrees.
we are given the degrees and we need to ad them up
148+90+120+129+130+142=749
then we subtract 749 from 900 which looks like
900-749=141
from subtracting 749 from 900 we get 141 hence we get our answer that m<B = 141 degrees