C your welcome tell me if u need more help
Answer:
1. Alternate angles, 2. Right angle, 3. Acute Angle, 4. Reflex angle
Step-by-step explanation:
0-2+9=7 is the answer I think
Answer:


let us first take a look at the values of the trigonometric ratios given in the question so that we get quite clear about what is to be done.
here ,

now ,
we just have to plug in the values considering certain other things given in the question and we're done!
so let's start ~

hence , proved ~
hope helpful :D