1/4= 0.25
2/4= 1/2 = 0.5
0.25 x 0.5 = 0.125
0.125 = 1/8
ANSWER
Eva is correct because 13/2 + 3/2 = 8
There is no mistake. Dakota may have thought that there was a mistake because Eva simplified when she got the answer for 4x which is correct but Dakota may have thought that it was incorrect.
I believe the answer is C
Step-by-step explanation:





Note: I used the identity

for the last step.
PS. I love proving trigonometric identities!