Answer:
2.8
Step-by-step explanation:
using cosine rule
= 
s =
= 2.842 = 2.8
2/3 is .666666 so that would be the percent
In this case, you need to find the percentage each student got, then find who received a higher score.
First Step:

(and)

Second step: Divide each fraction → ≈ 0.8947 (and) ≈ 0.8421
Third Step: Multiply each decimal by 100. → 89.47% (and) 84.21%
Fourth Step: As 89.47% is greater, Author got an higher score.
BRAINLIEST PLS!!!
Answer:
SO... whats the actual question?
Step-by-step explanation: