How many types of protenies are there in all life as we know it

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1

What accounts for an increase in the temperature of a gas that is kept at constant volume? a. energy has been removed as heat from the gas. b. energy has been added as heat to the gas. c. energy has been removed as work done by the gas. d. energy has been added as work done by the gas.

Ahair dryer is basically a duct in which a few layers of electric resistors are placed. a small fan pulls the air in and forces it through the resistors where it is heated. air enters a 1200 w hair dryer at 100 kpa and 22°c and leaves at 47°c. the cross-sectional area of the hair dryer at the exit is 60 cm2. neglecting the power consumed by the fan and the heat losses through the walls of the hair dryer, determine (a) the volume flow rate of air at the inlet and (b) the velocity of the air at the exit.