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Consider the function f(z) - 4(x - 3) . For this function there are two important intervals: ( - co, A) and ( A, co) where A is a critical number. A is For each of the following intervals, tell whether f(I ) is increasing or decreasing. ( - 00, A): Select an answer v (A, oo): Select an answer v For each of the following intervals, tell whether f( ) is concave up or concave down. ( - Do, A): Select an answer V (A, co): Select an answer V