ISTG I NEED HELP PLS SOMEONE I BEG mary swims 14 laps during her swim lesson and jimmy swims 18. if they begin swimming at the same time, how many laps with they meet each other?

HEL

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6