This document includes questions and answers that pertain to the ARPA-E Funding Opportunity Announcement (FOA) entitled "DE-FOA-0001953 Solicitation on Topics Informing New Program Areas Topic R - Lowering CO2: Models to Optimize Train Infrastructure, Vehicles, and Energy Storage (LOCOMOTIVES)".  The full Solicitation on Targets Informing New Program Areas FOA and additional information can be found on the ARPA-E Funding Opportunity Exchange website (https://arpa-e-foa.energy.gov/).