Bernie is showing Margaret his new boat and its autonavigation feature, of which he is particularly proud. “That island is 1 km east and 3 km north of this dock. So I just punch in the numbers like this, and we get ourselves a refreshment and enjoy the scenery." Forty-five minutes later, they find themselves due east of the island. "OK, something went wrong. I'll just reverse the instructions, and we'll go back to the dock and try again." But 45 min later, the boat is 6 km east of their original position at the dock. "Did you allow for the current?" asks Margaret. "For the what?"

(a) What is the velocity of the current in the waterway where Bernie and Margaret are boating?

(b) What is the velocity of the boat, r elative to the water, for the first 45 min?

(c) What is the velocity of the boat relative to the island for the first 45 min?