A box of cornflakes has a mass of 350g. A new box is brought out which states "contains 15% extra".What is the mass of the new box? CAN SOMEONE HELP ME PLEASE IAM STUCK

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