When considering how pressure responds to changes in temperature and altitude, under the assumption that other parameters remain constant, the correct answer is:
(d) decreases, decreases
As altitude increases, the pressure decreases. This is because there is less air above you, meaning there is less weight of air pressing down. Consequently, as you go higher in the atmosphere, the density of the air decreases, leading to lower pressure.
Additionally, when temperature increases, the pressure also tends to decrease when altitude is also increasing. This is due to the ideal gas law, where increasing temperature at a constant volume results in an increase in gas expansion and thus a decrease in pressure if the volume and moles of gas don’t change.
In summary, both factors—an increase in temperature and an increase in altitude—contribute to a decrease in pressure.