4. Two students walk in the same direction along a straight path, at a constant speed -- one at 9 m/s and the other at 1.9 m/s
2. Assuming that they start at the same point and the same time, how much sooner does the faster
student arrive at a destination 780 m away?
b. If student I increases his speed to 1.2 m/s, how much sooner does the faster student arrive at the same
destination?

First answer marked as brainiest which is the correct equation describing the first law of thermodynamics? a) when the internal energy of a system changes, it equals the amount of heat added plus the work done. b) when work is done by the piston, it is equal to the heat added plus the change in internal energy of the system. c) when heat is added to the system, it is equal to the amount of work done by the piston plus the change in internal energy of the system.