Differentiate each of the following voltage functions with respect to time and hence determine the 'rate of change' for each of the functions when time (t) is 5 seconds. \text

{ a) } v=\left(t^{2}+6\right)^{2} \text { b) } v=\left(3 t^{3}-4 t+6\right)^{3} \text { c) } v=\log _{e}(2 t) \text { d) } v=4 e^{-0.5 t} \text { e) } v=\sin \left(2 t^{3}+4 t-2\right) \text { f) } v=\cos \left(3 t^{4}-5 t+4\right)