Atrain approaching a crossing changes speed from 10 m/s to 25 m/s in 240 s. how can the train’s acceleration be described? a. the train’s acceleration is positive. b. the train is not accelerating. c. the train’s acceleration is negative. d. the train will come to rest in 6 minutes.

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What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?

Air initially at 0.75 bar, 1000 k, and occupying a volume of 0.12 m^3 undergoes two processes. process 1-2: the air is compressed isothermally until the volume is halved. process 2-3: the air undergoes a constant pressure process until the volume is halved again. assume ideal gas behavior. a) determine the mass of the air, in kg. b) the work and the heat transfer for each of the two processes, in kj. (100 kj = 1 bar . m^3)