Did they indeed put the ElectricCar class inside of the Car class? If that's the case, that's probably the problem. Normally when you extend a class you don't place the extending class inside the original class (actually, it's not often that a class gets placed inside another class). If it's suppose to be placed inside, then the two calls to the ElectricCar constructors are incorrect. They must be referenced from an existing instance of the Car class. For example:
myElec1 = myCar1.new ElectricCar();
As for the Car constructors, look at the ones declared inside the Car class and the ones invoked. do the signatures match up?
Ex., these would match up:
public SomeClass(String a)
// to call 1st constructor
SomeClass c = new SomeClass("hello");