The pressure, p, of a gas varies inversely with its volume, v. pressure is measured in units of pa. suppose that a particular amount of a gas is initially at a pressure of 104 pa at a volume of 108 l. if the volume is expanded to 432 l, what will the new pressure be

The pressure of a gas varies inversely with its volume.

In this case, the gas have 108L volume in 104pa pressure and you asked how much the pressure if the gas made into 432L volume. Since the volume is bigger it should be clear that the pressure would be lower.
The equation of the new pressure would be : 104pa x (108L / 432L) = 104pa x 0.25= 26pa

26pa

Ithink if im not mistaking b is -3 but im not a 100% sude

Not sure what the question is?