Teresa and susan have been given with four cards with four different functions on them.
function a: f(x) = 3^x +1

function b: f(x) = 3(x+100)

function c: f(x) = 30x+2

function d: f(x) = 0.3^x + 1000
teresa thinks that function d always exceed the other functions. susan doesn't think that teresa statement is true. which values of x disprove her claim? explain.