The Relationship between hours of practice influencing in a foreign language for class of students as shown any scatterplot Which craft most closely approximate the line of best fit for the Data can some one help me please

Arunning track in the shape of an oval is shown. the ends of the track form semicircles. a running track is shown. the left and right edges of the track are identical curves. the top and bottom edges of the track are straight lines. the track has width 56 m and length of one straight edge 130 m. what is the perimeter of the inside of the track? (π = 3.14) 260.00 m 347.92 m 372.00 m 435.84 m

Assume that the weights of quarters are normally distributed with a mean of 5.67 g and a standard deviation 0.070 g. a vending machine will only accept coins weighing between 5.48 g and 5.82 g. what percentage of legal quarters will be rejected? round your answer to two decimal places.

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .