Some courses assign letter grades, whereas other courses assign a percentagebetween 0 and 100. Still others assign a pass/fail grade. Write an interface named Grade. The toPercent method returns the grade asan integer percentage between 0 and 100 percent. The toString methodprints the grade in its "native" format (a percentage, a letter grade, or either"Pass" or "Fail"). The isPass method returns true for a passing grade, false otherwise. The includeInAverage returns true for letter andnumeric grades, but false for pass/fail grades. Write three classes that implement Grade: LetterGrade, PercentageGrade, and PassFailGrade. Write a main method that fills an array with grades. Foreach grade, print on one line the native format, "Pass" or "Fail" (as appropriate),and the percentage (if it can be included in an average). After the list ofgrades, print the average grade as a percentage. Use your school’s mapping between letter grades and numeric grades, if it hasone. Otherwise, make up something like A+ is 95%, A is 90%, etc.