Identify the illegal identifier from the following.

1. _CHK
2. αβγτ
3. 20to50
4. AtoZ

Which of the following does not represent a character literal ?

1. 'a'
2. '1'
3. '\a'
4. "a"

ch += 2 is equivalent to

1. ch = ch + 2
2. ch + 2
3. ch =+ 2
4. none of the above

The Math class is part of which Java library package.

1. java.util
2. java.io
3. java.random
4. java.lang