If the average grade of an english class rose from 70to85 what is the approximate percent increase
a the percent increase is 14%
b the percent increase is 17%
c the percent increase is 21%
d the percent increase is 35%

The average number of vehicles waiting in line to enter a parking lot can be modeled by the function f left parenthesis x right x squared over 2 left parenthesis 1 minus x right parenthesis endfraction , where x is a number between 0 and 1 known as the traffic intensity. find the rate of change of the number of vehicles waiting with respect to the traffic intensity for the intensities (a) xequals0.3 and (b) xequals0.6.