Consider a packet from a source computer to a destination server through K=4 hops as shown in the below figure. The packet size is 1500 bytes. The link capacity of every hop is R=1 Gbps. The total length of the fiber cable over the 4 hops is 30 miles. Assume that the processing time and queue delay at each router is negligible. How much time does it need to send the packet from the source to the destination? [hint: calculate transmission and propagation delays.]