[Solved] I am not sure what the following is expecting for

Question

You need a contructor, or setting all values before trying to get them or there will be null pointers

public MotorBoat(double a, double b, double c /* etc*/){
    this.a = a;
    this.b = b;
    this.c = c;
}

also returning amunt used needs to have the () removed in the return else you are refering to the function, not the temporary variable you created in the function

Finally you need to have getters and setters for all values that are private you wish to acces from outside the class, say on an instance of the class, and then use these functions when operating on the class in a non-class scope, say your static manin in this case

Next time you ask a question, please specify the error, and what you are looking for help with, there is nothing wrong with asking for help with homework per say, but there is unless you show you tried and provide a describtion of what you need help with

Accepted Answer

You need a contructor, or setting all values before trying to get them or there will be null pointers

public MotorBoat(double a, double b, double c /* etc*/){
    this.a = a;
    this.b = b;
    this.c = c;
}

also returning amunt used needs to have the () removed in the return else you are refering to the function, not the temporary variable you created in the function

Finally you need to have getters and setters for all values that are private you wish to acces from outside the class, say on an instance of the class, and then use these functions when operating on the class in a non-class scope, say your static manin in this case

Next time you ask a question, please specify the error, and what you are looking for help with, there is nothing wrong with asking for help with homework per say, but there is unless you show you tried and provide a describtion of what you need help with