Part a

Write the static method numberOfLeapYears, which returns the number of leap years between year1 and year2, inclusive. In order to calculate this value, a helper method is provided for you. • isLeapYear(year) returns true if year is a leap year and false otherwise. Complete method numberOfLeapYears below. You must use isLeapYear appropriately to receive full credit. /** Returns the number of leap years between year1 and year2, inclusive.

  • Precondition: 0 <= year1 <= year2 */ public static int numberOfLeapYears(int year1, int year2)
public static int numberOfLeapYears(int year1, int year2) {
    for(int i = year1; i <= year2; i++){
        int countLeapYears=0;
        if(isLeapyear(i)){
            countLeapYears+=1;
        }
        return countLeapYears;
    }
}

Part b

Complete method dayOfWeek below. You must use firstDayOfYear and dayOfYear appropriately to receive full credit. /** Returns the value representing the day of the week for the given date

  • (month, day, year), where 0 denotes Sunday, 1 denotes Monday, …,
  • and 6 denotes Saturday.
  • Precondition: The date represented by month, day, year is a valid date. */ public static int dayOfWeek(int month, int day, int year)
 public static int dayOfWeek(int month, int day, int year){
    int startDay = firstDayOfYear(year);
    int nthDay = dayOfYear(month, day, year);
    int returnDay = (startDay + nthDay - 1) % 7;//start day + number of days plus leftover days are used to calculate final day
    return returnDay;
}