$5.$ Answer the following questions about value range.

a$.$ what is the formula for the maximum value representable by an n$-$bit unsigned binary?

b$.$ what is the maximum value expressible by a $11-$bit unsigned binary?

c$.$ what is the value range $($min and max$)$ of an unsigned $5-$digit hexadecimal?

d$.$ could a $4-$digit hex represent more$/$less$/$equal values than a $16-$bit binary?