GMAT Test Prep: DS-89434847 GMAT Data Sufficiency

While on straight, parallel tracks, train A and train B are traveling at different constant rates. If train A is currently 2 miles behind train B, how many minutes from now will train A be 4 miles behind train B?

1. Three minutes ago, train A was 1 mile behind train B.

2. Train A is traveling at 80 miles per hour, and train B is traveling at 100 miles per hour.
Select one of the following answer choices