In ABC, the interior angle at A is 51° and the exterior angle at B is 119º. The interior angle at C measures A 51°
B 68°
C 90°
D 39°

68 degrees

Step-by-step explanation:

To get the interior angle, we use an important triangle principle

The principle is that the sum of the opposite interior angles equal the exterior angle

Let the second interior angle be x

x + 51 = 119

x = 119-51

x = 68

2 is the final ! : )