Solve the all parts of following problem given below:
Problem: A river flows due south with a speed of 1.9m/s. A man steers a motorboat across the river; his velocity relative to the water is 4.2m/s due east. The river is 680m wide.
Part I- What is the magnitude of his velocity relative to the earth? Express your answer using two significant figures.
Part II- What is the direction of his velocity relative to the earth? Express your answer using two significant figures.
Part III- How much time is required to cross the river? Express your answer using two significant figures.
Part IV-How far south of his starting point will he reach the opposite bank? Express your answer using two significant figures.
This is a physic problem, reply as soon as possible. Thank you.