A program is divided into 3 blocks that are being compiled on 3 parallel computers. Each block takes an Exponential amount of time, 5 minutes on the average, independently of other blocks. The program is completed when all the blocks are compiled. Compute the expected time it takes the program to be compiled.

Idon understand these and need some ! ?

1. which of the following statements are true about routers and routing on the internet. choose two answers. a. protocols ensure that a single path between two computers is established before sending packets over it. b. routers are hierarchical and the "root" router is responsible for communicating to sub-routers the best paths for them to route internet traffic. c. a packet traveling between two computers on the internet may be rerouted many times along the way or even lost or "dropped". d. routers act independently and route packets as they see fit.

20 points archie wants to use a reflector as he photographs a newlywed couple. what would he consider in his choice? a. shadow and sunny b. homemade and professional c. lamps and boards d. incident and reflected e. neutral density and enhancement