Need help. I found a solution on chegg already, but it says error. The code didnt work

Java language

3 Consider a class MotorBoat that represents motorboats. A motorboat has attributes for .The capacity of the fuel tank The amount of fuel in the tank . The maximum speed of the boat The current speed of the boat The efficiency of the boat's motor The distance traveled The class has methods to Change the speed of the boat Operate the boat for an amount of time at the current speed . Refuel the boat with some amount of fuel . Return the amount of fuel in the tank Return the distance traveled so far If the boat has efficiency e, the amount of fuel used when traveling at a speed s for time t is e s t. The distance traveled in that time is s a. Write a method heading for each method. b. Write preconditions and postconditions for each method. c. Write some Java statements that test the class. d. Implement the class