Superman is flying 54.5 m/s when he sees a train about to fall into a river 850 m away. he must reach the train in 4.22 s. what acceleration does he need? (unit = m/s^2)

Achemistry student needs of 40ml diethylamine for an experiment. by consulting the crc handbook of chemistry and physics, the student discovers that the density of diethylamine is 0.7 . calculate the mass of diethylamine the student should weigh out. round your answer to significant digits.

Two technicians are discussing a resistance measurement between the can-h and can-l wires. technician a says this measurement should be done with the ignition switch in the "run" position. technician b states that a measurement of 0 ohms indicates an open in the network. which technician is correct?

What distance does a car travel as its speed changes from 0 to 20 m/s in 17 s at constant acceleration?