Answer the following questions and show how you arrived at your answers.

a$.$ What is the network ID portion of the IP address $4\mathrm{.}5\mathrm{.}6\mathrm{.}7$ with mask $255\mathrm{.}192\mathrm{.}0\mathrm{.}0?$ Express your answer in binary.

b$.$ What is the host ID portion of the IP address $4\mathrm{.}5\mathrm{.}6\mathrm{.}7$ with mask $255\mathrm{.}255\mathrm{.}255\mathrm{.}0?$ Express your answer in binary.

c$.$ What is the address range covered by the CIDR block $128\mathrm{.}8\mathrm{.}16\mathrm{.}0/20?$ Express your answer indecimal octet format.