A planar structure of length £ and width W is made of two different optical media of refractive indices $$n_1 = 1.5 and n_2 = 1.44$$ as shown in figure. If $$L \gg W$$, a ray entering from end AB will emerge from end CD only if the total internal reflection condition is met inside the structure. For L = 9.6 m, if the incident angle $$\theta$$ is varied, the maximum time taken by array to exit the plane CD is $$t \times 10^{-9} s$$, where t is _______.
[ Speed of light $$c = 3 \times 10^8 m/s$$]