Answer:
`18. x=9
19. x=4
20. x=25,5
21. x=3
22. x=3,5
23. x=10
Step-by-step explanation:
or 
Step-by-step Explanation :
As the given fraction is an improper fraction, it is hard to divide properly. Either :
☆ You can write what it is given as per question for the answer.
☆ Else, by dividing, we will get a huge value. In this case, we get it as 
The correct answer would be B
1. 50 degree angle I believe
2. 150 degree angle
3. 45 degree angle
Sorry if this doesn't help but, with no context about the answers they have given you I can't fully help. Try using a protractor like this down below.
Have a good day!