Two devices H1, and H2 are part of LAN. The devices are not directly connected to each other. They are separated by a router (R). The length of the first link (H1—R) is 50 Km and the length of the second link (R—H2) is 20 Km. The propagation speed for the first link is 2.4x108 m/s and for the second link 2x108 m/s. The bandwidth of the first link is 5 Mbps and the bandwidth for the second link is 1Gbps.
Assume H1 is sending a file of size 30 Mbyte in one message. When H2 receives the message, it has to send a special message called acknowledgment. Since the acknowledgment message is very small in size its transmission time is always ignored.

What will be the total time needed for H1 to receive the acknowledgment from H2, once H1 starts sending the first bit of the file?