SOLUTION
The angles marked in red in the picture below are the missing angles
Figure A
In figure A angles on a straight line is 180. So subtract 50 from 180 to get angle DAE as 130 degrees
In figure B, vertically opposite angles are equal so angle HEI is 30 degrees.
To get the other 150 degrees, subtract the sum of the two vertical angles which makes 60 from 360 degrees (angles at a point) to get 300 degrees, then divide by 2 to get the other two 150 degrees angle
Same process in Figure A applies to figure C
Also same process in figure B applies to figure D