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A hollow container is filled with an Ideal gas. The container is designed to maintain a constant pressure by allowing gas to enter or leave as needed. At all times the gas & container are in thermal equillbrium. Initially the temperature is $750$ K $.$ Then the temperature decreases to $300K$ and the volume decreases to $0\mathrm{.}86$ times the initial volume. Determine the coefficient of volume expansion for the container and the ratio of the final number of moles to the initial number of moles.

${}_{\text{c}\text{o}\text{n}\text{t}\text{a}\text{i}\text{n}\text{e}\text{r}}=q,K^{-1}$

$\frac{n_f}{n_i}=$

$q,$