I think it would be B /C I’m so sooo sorry if I’m wrong but um I don’t take this math anymore :)
Eliminate the parameter t:t=y/2
x=y^2/2+3
I'm sorry I'm too lazy to read all of that. However, I did get the main point. The river was going at 3 mph. Since he wanted to travel 10 miles upstream and downstream, you would have to subtract 20 by 3. This would mean he was going at a speed of 17 mph.
What is the price of the individual boxes?