Final answer:
Water skiers can use hand signals or two-way communication devices like waterproof radios or headsets to communicate with the tow boat.
Step-by-step explanation:
Water skiers can use hand signals or a two-way communication device to communicate with the tow boat.
Hand signals are commonly used as a non-verbal form of communication between water skiers and the tow boat. Skiers can use different hand gestures to indicate whether they want to speed up, slow down, turn, or stop.
Alternatively, water skiers can also use two-way communication devices, such as waterproof radios or headsets, to communicate directly with the tow boat operator. These devices allow skiers to talk to the boat operator and receive instructions or relay any concerns or issues.