A right triangle is a triangle with one 90 degree angle; the triangle that appears to have a right angle is D/ the option on the very bottom.
I do believe it would be 12 percent, if rounded.
In the problems A-F, You multiply each of the numbers by itself. Like 9²=9×9=81
3³=3×3×3=27 6³=6×6×6=216 and so on for the other problems
G-I is 36=6² 100=10² and so on the cube is the same except you multiply the number three times by itself. I hope this helped a bit. Just ask if you still don't understand.
For f(x), 6 represents x here, so we plug 6 in for x to get 2*6²+5√(6-2). Using PEMDAS, we get 72+5√4=72+5*2=72+10=82