What is the answer to 4 and 5? I need help quick.

Aboat has a speed of 9 mph in calm water. it takes the boat 4 hours to travel upstream but only 2 hours to travel the same distance downstream. which equation can be used to find c, the speed of the current? 2(9 – c) = 4(9 + c) 9 + c = 4(9 – c) 9 – c = 2(9 + c) 4(9 – c) = 2(9 + c)

Ken leaves work 20 minutes late. he decides to make up time by taking the toll road instead of side streets. he can travel three times faster by taking the toll road. create an equation to represent his total travel time, including wait time, where x is the number of minutes the drive was expected to take

Lm is the midsegment of trapezoid abcd. if ab=46 and dc=125, what is lm?