a Applying the two step Adam Bashforth method see Lec 8 to approximate y 2 5 where y is the solution to y 1 y 1 t 1 5 y 1 1 with h 0 5 You may use Euler s method to get the starting value at t 1 5 exact solution is y t 2t 1 b Compare your approximation with the exact solution write down your observation and try to explain why very briefly optional