Which keyword turns a variable declaration into constant declaration ?

1. const
2. constant
3. final
4. fixed

ch += 2 is equivalent to

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

Which clause is optional in a switch statement?

1. switch
2. case
3. default
4. none of the above

Absence of which statement causes a fall-through in a switch statement.

1. continue
2. break
3. stop
4. fall