AMO 2016 Secondary 1 (Grade 7) Question 10

Suppose $x=+\frac12$ and $y=-\frac14$. Select the number of the expression having the numerically greatest result: (1) $x+y$; (2) $x^2-y$; (3) $x^2+y$; (4) $x-y$; (5) $y-x$. Enter its original number, from 1 to 5.