D) The measures of the non- right angles in each triangle .
Answer:
This is an improper fraction so we need to make it a mix fraction.
Step-by-step explanation:
21/10 = 10/10+10/10+1/10
10/10=1
So your final answer will be 
Hi there!
»»————- ★ ————-««
I believe your answer is:
Option A
»»————- ★ ————-««
Here’s why:
⸻⸻⸻⸻

⸻⸻⸻⸻

⸻⸻⸻⸻

⸻⸻⸻⸻

⸻⸻⸻⸻
»»————- ★ ————-««
Hope this helps you. I apologize if it’s incorrect.