1. (a) Given the Heat Equation below Ju -av²u=0 at explain under what circumstances this equation reduces to the Laplace equation. 5 marks (b) The equation below models the flow of current for a submarine cable J²i di = RC მე-2 Ot Solve the equation for a cable of length 0.90m with values of R = 80 and C = 1μF subject to the Boundary conditions at i=0 at x=0 and x=L, and the initial condition at t=0. 25 Marks i(x,t) = 7sin +11sin 0.30 0.45