The forward, backward Euler as well as the Trapezoidal and the Heun's methods are the four methods that you have learned in this course to solve ordinary differential equations (ODES). A numerical simulation of a first order ODE via an explicit method using stepsizes 2h and h results in the following errors: E2h = 0.101, En = 0.2 Which one of the above methods is used in this simulation ? Motivate your answer! Another numerical simulation of a first order ODE via an implicit method using stepsizes 2h and h results in the following errors: E2h = 0.01001, En = 0.00253 Which one of the above methods is used in this simulation ? Motivate your answer!