; (2) among other safety factors with respect to such trains, an evaluation of— (A) any increased risk of loss of communications between the end of train device and the locomotive cab, including communications over differing terrains and conditions; (B) any increased risk of loss of communications between crewmembers, including communications over differing terrains and conditions; (C) any increased risk of derailments, including risks associated with in-train compressive forces and slack action or other safety risks in the operations of such trains in differing terrains and conditions; (D) safety risks associated with the deployment of multiple distributed power units in the consists of such trains; and (E) impacts of the length of trains on braking and locomotive performance and track wear and tear; and (3) an evaluation of whether additional engineer and conductor training is required for safely operating such trains. (c) Report Not later than 18 months after the date of enactment of this Act, the Secretary shall submit to the Committee on Transportation and Infrastructure of the House of Representatives and the Committee on Commerce, Science, and Transportation of the Senate a report on the results of the study. (d) Funding From the amounts made available for fiscal year 2021 to carry out section 20117(a) of title 49, United States Code, the Secretary shall expend not less than $1,000,000 and not more than $2,000,000 to carry out the study required under subsection (a). 9502. GAO study on changes in freight railroad operating and scheduling practices (a) Study The Comptroller General of the United States shall study the impact on freight rail shippers, Amtrak, commuter railroads, railroad employees, and other affected parties of changes in freight railroad operating and scheduling practices as a result of the implementation of the precision scheduled railroading model. (b) Contents At minimum, the study shall examine— (1) the impacts of the operation of longer trains