PLEASE HELP !! Reaction time + ? = Speed

Coordination Time
Mental Reaction Time
Physical Reaction Time
Movement Time

Truck traveling west on the highway experiences an acceleration to the east. what could be the cause of this acceleration

An inclined plane wrapped around a metal shaft is a a. lever b. screw c. pulley d. wedge

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.