What is the minimum number of bits needed to represent the following decimal numbers in binary?

$1\mathrm{.}9$ Repeat $\frac{?}{{?}_{\frac{?}{?}}}$ Problem $1\mathrm{.}8$ for the following decimal numbers:

$($a$)(111{)}_{10}$

$($b$)(333{)}_{10}$

$($c$)(555{)}_{10}$

$($d$)(1111{)}_{10}$