Ahigh-definition tv has 1920 columns and 1080 lines of resolution. a us standard definition tv has has 640 columns and 480 lines. how many times more pixels are there in hd compared to sd?

Which is a false statement considering copyright law? a. when people upload something to the internet they automatically receive a copyright for the work b. the work does not have to contain a copyright notice to be considered having a copyright c. copyright is legal term describing rights given to the creators for literary and artistic works d. personal pictures are always covered by copyrights

Consider a slotted aloha system, where the time slot equals the fixed duration of each packet. assume that there are 4 stations a,b,c,d sharing the medium. (a) stations a,b,c,d receive one packet each from higher layers at times 1.3, 1.5, 2.6,5.7 respectively. show which transmissions take place when, according to the slottedaloha protocol; describe all transmissions until all four packets have been successful.when needed, each station has access to the following sequence of random number, provided by a random number generator and drawn uniformly between 0 and 1: (1) station a draws numbers: 0.31, 0.27, 0.78, 0.9, 0.9, 0.11, 0. (2) station b draws numbers: 0.45, 0.28, 0.11, 0.83, 0.37, 0.22, 0. (3)station c draws numbers: 0.1, 0.2, 0.3, 0.4, 0. (4) station d draws numbers: 0.36, 0.77, 0.9, 0.1, 0.1, 0.1, 0.1, 0. (b) in slotted aloha, a station transmits in each time slot with a given probability. what probabilities would you assign to each of the four stations so as to: (i) maximize the efficiency of the protocol? (ii) maximize fairness among the four stations? (c) will the efficiency increase or decrease if we modify slotted aloha as follows: (i) get rid of slots and allow stations to transmit immediately? (ii) implement carrier sensing? (iii) implement collision detection? (iv) implement collision avoidance?

Alex’s family members live in different parts of the world. they would like to discuss the wedding plans of one of their distant relatives. however, alex wants all the family members to talk to each other simultaneously so that they can make decisions quickly. which mode of internet communication should they use? a. blog b. email c. wiki d. message board e. instant messaging