Use the phase diagram below to answer the following.

a$)$ What are the approximate temp and pressure of the critical point?

b$)$ What are the approximate temp and pressure of the triple point?

c$)$ If solid methane at $1$ atm is heated while the pressure is held constant, will it melt or sublime?

d$)$ Is methane a solid, liquid or gas at $1$atm and $0C?$

e$)$ If methane at $1$atm and $0C$ is compressed until a phase change occurs, in which state is the methane when the compression is complete?

FIGURE $11\mathrm{.}30$ Phase diagram of $C{H}_4.$ Note that a linear scale is used to represent temperature and a logarithmic scale to represent pressure.