On a certain day of the week, we took a taxi to the store. Can someone please help me I don't know how to change it to proper.

What task did the surveyors do? a. they studied the landscape to determine the most direct route for building a road. b. they designed treadmills that lifted blocks of stone to where they were needed. c. they dug trenches and filled them with sand, concrete, and large blocks to form a road.