Acar is stopped at an entrance ramp to a freeway; its driver is preparing to merge. at a certain moment while stopped, this driver observes a platoon of vehicles a distance x0 upstream and initiates the merge maneuver. the platoon approaches the entrance ramp at a constant speed v. the stopped car can accelerate from speed 0 to v at uniform acceleration rate a. find the latest time at which the stopped car can safely start the merge maneuver; i. e., derive an expression for the "latest safe start time" in terms of the variables x0, v and a. assume this latest time enables the platoon to maintain its constant speed and "just touch" the merging car's trajectory. ignore the physical dimensions of the car.