Consider the initial value problem    dy dt = y + t y(0) = 0 (7) (a) approximate y(0.5) using euler’s method with stepsize ∆t = 0.25. (b) approximate y(0.5) using euler’s method with stepsize ∆t = 0.1. (c) find the exact solution of the differential equation and use it to compute the exact value of y(0.5). are the approximations from parts (a) and (b) over-approximating or under-approximating the value of y(0.5)? explain why this occurs.