1. Which of the following functions is (are) partial?

a.	f(x) = if x>3 then 3*x else 0

b.	f(x) = if x < 0 then f(-x) else 1/x

c.	f(x) = if x > 0 then f(-x) else f(-2x)

d.	f(x) = x+1

2. Implement a program that does not halt. You can use a language of your choice.