4.13 -
public multiConcat(String str, int num1)
{
if (num1<2) return str
else for (int count = 2; count <= num1; count++)
result += text;
}
 public multiConcat(String str)
{
return str.concat(str);
}

4.14 -
public char isAlpha(char letter)
{
Character tester = new Character() ;
tester = letter.toUpperCase() ;
if (letter.equals(tester)) return “Uppercase”
else return “Lowercase” ;
}

4.15 -
public float floatEquals(float n1, float n2, float n3)
{
if (Math.abs(n1 - n2) <= n3) return true
else return false ;
}