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Yes, we can determine the sum of two interior angles of the triangle, that are not supplemental to the given exterior angle.
This sum is equal 120°.
It is based on this Theorem (see the lesson Sum of the interior angles of a triangle in this site):
An exterior angle of a triangle is equal (is congruent) to the sum of the two angles
of the triangle that are not supplemental to the given angle.
Again, we can determine the sum of measures of two interior angles of the triangle, that are not supplemental to the given exterior angle.
But we can not determine the measures of each of these two angles separately/individually.