Let us consider the PDE Uxx + 3utt - Uz Ut = t with the initial conditions u(x, 0) = 0 , u(x, 0) = 1. If we use Laplace transform for this PDE, which of the following will be the coefficient of U (x,s)? A s +s s2 - s B C s2 + 2s D 3s2 s | s2 2s