AMC 10B 2015 Problem 2

Marie does three equally time-consuming tasks in a row without taking breaks. She begins the first task at 1:00 PM and finishes the second task at 2:40 PM. When does she finish the third task?

Answer Choices
A. 3: 10 \mathrm{PM}
B. 3: 30 \mathrm{PM}
C. 4:00 PM
D. 4:10 PM
E. 4:30 PM