Assume propagation speed in copper and fiber to be 9/10 the speed of light in vacuum....

A factor in the delay of a store-and-forward packet-switching system is how long it takes to store and forward a packet through a switch. If switching time is 40usec, is this likely to be a major factor in the response of a client-server system where the client is in New York and the server is in California? Assume propagation speed in copper and fiber to be 9/10 the speed of light in vacuum. Now consider 5 switches between the client and server, how does this affect the calculation