A shopping mall manager creates a parabola to predict the number of shoppers in a mall, where $x$ is the number of hours since 8 A. M. And $y$ is the number of shoppers in the mall. Write a function $f$ that models the number of shoppers in the mall over time. Then find the average rate of change in the number of shoppers over the interval in which the number of shoppers is increasing. Round your answer to the nearest whole number.

10 ! in a race, nick is 50 feet in front of jay after ten seconds. how fast can nick run, if jay can run 20 feet per second?

Ellen makes and sells bookmarks. she graphs the number of bookmarks sold compared to the total money earned. why is the rate of change for the function graphed to the left?

According to a study conducted in 2015, 18% of shoppers said that they prefer to buy generic instead of name-brand products. suppose that in a recent sample of 1500 shoppers, 315 stated that they prefer to buy generic instead of name-brand products. at a 5% significance level, can you conclude that the proportion of all shoppers who currently prefer to buy generic instead of name-brand products is higher than .18? use both the p-value and the critical-value approaches.