Sin = opposite/hypotenuse, so one side is 7 and the other is 8.
sqrt(64-49)=sqrt(15) which is the third side, and tangeant = opposite/adjacent, which is 7/sqrt(15). Cotangeant is 1/tangeant, so it would be sqrt(15)/7
<span>percent ---------------- quantity
Acid type I 60.00% ---------------- x liters
acid type II 30.00% ------ 60 - x liters
Mixture 40.00% ---------------- 60
Total 60 liters
60.00% x + 30.00% ( 60 - x ) = 40.00% * 60
60 x + 30 ( 60 - x ) = 2400 </span>
The answer is A zinc is oxidized and copper gets reduced