Q$-20.$ Combine the following three blocks of addresses into a single block with the same prefix length. The combined block, which uses the minimal address space, should cover all addresses already assigned in the three blocks.

$16\mathrm{.}27\mathrm{.}24\mathrm{.}0/26$

$16\mathrm{.}27\mathrm{.}24\mathrm{.}64/26$

$16\mathrm{.}27\mathrm{.}24\mathrm{.}128/25$

Write the first and last address $($with subnet mask$)$ of