i dont suck or anything... im just stuck on those and i really cant figure em

6- a pressure of about 1,0 x 10^-13 Pa is near emptiness. What would be the number of molecules that 1L of gas would contain at that pressure and at 0 degrees celcius (273 kelvins)?

9- At what temperature (in degrees celcius) must we bring a gas that is initially at -50 degrees celsius (223 Kelvins), if we want to pinput it in a container thats 3 times bigger and that its pressure is 5 times lower?

10- The pressure created by the air in a tire is of 175 kPa for a day with a -5 degress celcius temperature. The manufacturer recomends a maximal pressure of 250 kPa. would the recomandation be respected if, on a summer day, the temperature would be of 40 degrees celcius (313 Kelvins)? Why? (we suppose that the volume does not change.)