6. Fill in all the angles in the following figure.

First fill in the alternate interior angle to the 30^o angle

Next, fill in the corresponding angle for the 50^o angle.

Since we know two angles in the bottom triangle, we can get the third by subtracting the sum of the first two from 180.

30 + 50 = 80

180 - 80 = 100

We can get the fest by filling in supplementary angles.