Answer
Domain: $ t\leq 2 $
Range: All real numbers.
Work Step by Step
Because we can only take the square root of values that are 0 or greater, we set $\sqrt (2-t) \geq 0 $
Square both sides to get $ 2-t \geq 0 $, then add t to both sides to get $t \leq 2 $.
The range of a square root function is all real numbers, because the root of the function includes both positive and negative values.
