Please answer this and show your solutions on paper.I will give you a very good feedback. on paper please :(

ON PAPER PLEASE ! ON PAPER !

1. A sample of air occupies a volume of 12.5 L at 30*C when the pressure is 0.987 atm. What would be its volume at the same temperature when the pressure is 2.96 atm? [ L] 2. A gas sample occupies a volume of 25.0 dm3 when it is confined by a pressure of 110.0 kPa at 27"C. What would be the pressure that should be applied to compress the gas to one-tenth of its initial volume? [ kPa] 3. A balloon contains 20.0 L of helium at a temperature of 30*C and a pressure of 1 atm. If the balloon is transferred to a room with a temperature of 20*C and the pressure is held at the same value, what would be the volume of the gas inside the balloon? [ L] 4. How many moles are contained in a gas sample which occupies a volume of 4.78 L at 273 K and 1.00 atm? [ mol]