Remember that things like this, always need to add up to 180°.
Answer:

Step-by-step explanation:
The scientific notation:

We have:

16/20
Simplified to 8/10
Again simplified to 4/5.
Answer: A, D, and E
Step-by-step explanation:
Basically, you want to divide each of these answers by 5. Which ever one gives you a solid number (meaning no decimals) then that would be one option.
Hope this helps!