Answer:



Step-by-step explanation:
Given



Required
The measure of each angle
First, we calculate the length of the three sides of the triangle.
This is calculated using distance formula

For AB





So:

For BC





For AC





So, we have:



By representation



So, we have:



By cosine laws, the angles are calculated using:







Collect like terms


Solve for 


Take arc cos of both sides





Collect like terms


Solve for 


Take arc cos of both sides


For the third angle, we use:
--- angles in a triangle
Make C the subject



Answer:
i would say B a stick shift
Step-by-step explanation:
1 and 2 are natural numbers
-7 belongs to set of integers
sqrt 11 is a member of the set of irrational numbers