A 0.3kg model rocket is loaded with 0.8kg of rocket fuel. After launch, the rocket rises at a constant rate of 4m/s, but the rocket fuel is dissipated at a rate of 0.15kg/s. Find the work done in propelling the rocket 20m above the ground. (Use 9.8m/s2 for g.) Find the work (in J) needed to lift the model rocket itself. (Ignore the work needed to lift the fuel.) 3 Show how to approximate the required work (in J) to lift the rocket fuel by a Riemann sum. (Let x be the distance in meters above the ground. Enter xi as xi.) limni=1n(x Express the work (in J ) required to lift the rocket fuel as an integral of x (in m ). 0l(dx Evaluate the integral (in J ). J Find the total work (in J) by adding the work of lifting the model rocket to the work of lifting the rocket fuel. J