HURRY PLEASE!!

What are dichotomous keys used for?

Science

Which of the following is considered to be a vector?               a.  temperature    b.  velocity    c.  time    d.  mass

In the sport of parasailing, a person is attached to a rope being pulled by a boat while hanging from a parachute-like sail. a rider is towed at a constant speed by a rope that is at an angle of 15 ∘ from horizontal. the tension in the rope is 1900 n. the force of the sail on the rider is 30∘ from horizontal. what is the weight of the rider? express your answer with the appropriate units.

What happens when you slowly pulled the carboard?