Consider a message that is

bits long that is to be sent from source to destination in the figure above and all the packet switch uses store$-$and$-$forward routing. Suppose each link in the figure is $2$ Mbps$.$ Ignore propagation, queuing, and processing delays. Now suppose that the message is segmented into $800$ packets, with each packet being $10,000$ bits long.

How long does it take to move the file from source host to destination host when message segmentation is used?

How long does it take when message segmentation is NOT used?