Carlos was tracking the increasing number of people walking down the street. At 6 a.m., there were 57 people. At 8 a.m., there were 65 people. If Carlos made the function f(x) = 4x + 33, what would the 33 represent? The rate at which the number of people was increasing The length of time he recorded for The number of people at midnight The total change in the number of people