Research shows that wearing your mask, and opening the front passenger window, and the window behind the driver seat helps to reduce the spread of the novel coronavirus in your vehicle. See this NY Times article.
My schedule is variable. But should reach work between 7 -9 am and need transport back home between 3-5 pm (8 hrs later). Need to carpool as I don't currently have a car and public transportation would take 2.5 hours each way.