Answer:
90 degrees
Explanation:
Ok so basically, first you see that angle 1 and a right angle are on a line together, and the angles on a straight line always have to add up to 180 degrees. This means that angle 1 = 180-90 = 90.
There's no way to tell the exact angle measure of angle 2 and angle 3, but you can figure out the sum. Since the interior angles of a triangle have to add up to 180, that means that 180 - 90(angle 1) = 90 for the sum of angle 2 and angle 3.