I need help pt2. I have a major grade due tomorrow and I have 12 questions left and idk how to solve the last 12

Modify the equation fδt=δ (mv) to find the force of friction.

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant

Air conditioners not only cool air, but dry it as well. suppose that a room in a home measures 5.0m×9.0m×2.4m . if the outdoor temperature is 30 ∘c and the vapor pressure of water in the air is 85 % of the vapor pressure of water at this temperature, what mass of water must be removed from the air each time the volume of air in the room is cycled through the air conditioner? the vapor pressure for water at 30 ∘c is 31.8 torr.