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He concluded that a heavier object dropped from the same height as a lighter object will land

The graph of a function f(x)=(x+2)(x-4). which describes all of the values for which the graph is negative and increasing? all real values of x where x< -2 all real values of x where -2

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25