Final answer:
The primary purpose of the MB-4 tug is to pull and move a barge. Tugboats provide the necessary force to move large vessels, such as barges, by exerting a pulling force on them.
Step-by-step explanation:
The primary purpose of the MB-4 tug is to pull and move a barge, as shown in the figure. Tugboats are used to provide the necessary force to move large vessels, such as barges, by exerting a pulling force on them.
In the given question, two tugboats are pulling the disabled vessel in different directions. By resolving the pulling forces into their scalar components, you can find the magnitude and direction of the resultant force pulling on the barge.