Rewrite the Following Nested If-Else Statements Using an Equivalent Switch

Rewrite the following nested if-else statements using an equivalent switch statement.
if (letter == 'A' || letter == 'a')
System.out.println("Excellent");
else if (letter == 'B' || letter == 'b')
System.out.println("You can do better");
else if (letter == 'C' || letter == 'c')
System.out.println("Try harder");
else if (letter == 'D' || letter == 'd')
System.out.println("Try much harder");
else System.out.println("Try another major! ");