Please help it would mean a lot !!

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

Find the equation using the point (4,8)

It took alice 5 5/6 hours to drive to her grandparents' house for . on the way home, she ran into traffic and it took her 7 3/8 hours. how much longer did the return trip take? write your answer as a proper fraction or mixed number in simplest form. the trip home took __hours longer. ?