Newton second law of motion relates to force, what, and acceleration

Which quantities are scalars? choose all that apply a.distance b.speed c. acceleration d.velocity

Steam enters an adiabatic diffuser at 150 kpa and 1208c with a velocity of 550 m/s. determine the minimum velocity that the steam can have at the outlet when the outlet pressure is 300 kpa.

How to tell if two objects are in thermal equilibrium 1.the objects have the same temperature 2.the objects are the same size 3.the objects are touching each other 4.the objects temperatures are changing