A 960-M Wide River Flows at 16 M/s as Shown

Short Answer

A 960-m wide river flows at 16 m/s as shown in the figure. Alice and John have a race in identical boats which each travel 20 m/s in still water. Alice leaves point A and steers so that she goes straight to point B directly across and then back to A. John leaves point A and steers up to point C (960 m upstream)and then returns to A.
(a)Which person arrives back at point A first?
(b)How much sooner than the loser does the winner arrive back at point A?