Host a is sending a file to host b. there are 3 links (therefore 2 switches) between the hosts. the file is segmented into packets of 40 bytes, with a 10 byte header added to each packet. each link has a transmission rate of 100 kbps and a speed of 1000 km per sec. the switches are 100km away from each other. host a is 50 km away from the first switch while host b is 150 km away from the second switch. data travels from host a to the first switch, on to the second switch and then to host b. what is the propagation delay (in seconds) when a packet of data travels between the 2 routers?