A stretch by a factor of 2 for the exponential growth function f(x)= a(nine-fourths) superscript x occurs when a = . a stretch by a factor of eleven-thirds for the exponential decay function f(x)= a(three-fifths) superscript x occurs when a = . a shrink by a factor of one-third for the exponential growth function f(x)= a(7)x occurs when a = . a shrink by a factor of two-fifths for the exponential decay function f(x)= a(two-ninths) superscript x occurs when a = .