# Calculating the pressure in a tyre?

Need some help with this question. I doesn't appear to be very difficult, but I'm having some problems trying to adjust the new pressure after the temperature change. An automobile tyre is inflated with air originally at 10 degrees Celsius and at normal atmospheric pressure (i'm guessing 101325 Pa).... show more Need some help with this question. I doesn't appear to be very difficult, but I'm having some problems trying to adjust the new pressure after the temperature change.

An automobile tyre is inflated with air originally at 10 degrees Celsius and at normal atmospheric pressure (i'm guessing 101325 Pa). During the process, the air is compressed to 28% of its original volume and the temperature is increased to 40 degrees Celsius.

a) What is the new tyre pressure?
b)After the tyre is driven at high speed, the tyre air temperature rises to 85 degrees Celsius and the interior volume of the tyre increases by 2%. What is the new tyre pressure (absolute) in pascals?

Even if you can only answer the first question, anything will be great. If I could that working is provided so that I know how to actually do it. Thanks :)