Answer:
2.8 units
Explanation:
Think of this distance as the hypotenuse of a right triangle that has a vertical leg and a horizontal one as well.
Going from P to Q, the change in x is 2 and the change in y is also 2.
Thus, by the Pythagorean Theorem, this desired distance is:
d = √(2^2 + 2^2) = 2√2 units, or 2.8 units