Lincoln high school has 98 teachers. of them 48 teachers, 9 of them teach math. one-fifth of them teachers teach math

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Two planes leave an airport at the same time, one flying east, the other flying west. the eastbound plane travels 20 mph slower. they are 1600 mi apart after 2 hr. find the speed of each plane.

Given f(x)= 9x+1 and g(x)=x^3, choose the expression (f*g)(x)