One angle in an obtuse isosceles triangle measures 40°. what are the measures of the other two angles?
70° and 70°
80° and 80°
40° and 100°
40° and 120°

An obtuse triangle has one obtuse angle, or an angle that measures more than 90° but less than 180°. Options 1 and 2 are not correct, because these are acute angles.
So, one of the angles must be 40°, and the other may be 100° or 120°.
The measures of the angles in a triangle add up to 180°.

The other two angles are 40° and 100°.