In this question we will use the Malus Law, the formula of it is I = lo*cos^2(alpha). We will say that the given percentage of the intensity of a polarized light wave passes through a polarizing filter is 14%.
I = Io*cos^2(alpha)
then cos^2(alpha) = 0.14 alpha = arccos(sqrt(0.14)) = 68.03°
The answer in this question is 68.03°