A path in a digital circuit$-$switched network has a data rate of $2\mathrm{.}5$ Mbps$.$ The exchange of $2000$ bits

is required for the setup and tear down phases. The distance between the two parties is $6500$ km$.$

Answer the following questions if the propagation speed is $2\mathrm{.}5$x$10^8$ m$/$s:

a$.$ What is the total delay if $1500$ bits of data are exchanged during the data transfer phase?

b$.$ What is the total delay if $120,000$ bits of data are exchanged during the data transfer

phase?