An AGV driverless train system is being planned for a warehouse. Each train will consistof the towing vehicle plus three pulled carts. Train velocity is $200$ ft$/$min$.$ Only the pulledcarts carry loads, one load per cart. The average loaded travel distance per delivery cycleis $2500$ ft and empty travel distance is the same. The anticipated traffic factor is $0\mathrm{.}95$ andavailability is $0\mathrm{.}98.$The load handling time per train per delivery is expected to be $7\mathrm{.}5$ min.If the requirements on the AGVS are $20$ loads per hour, determine the number of trainsrequired.