A single dimensional array can be declared as int a[10] or int a[] = {1, 2, 3, 4}. It means specifying the number of elements is optional in 1-D array. Given the array above, which statement would change the fifth element to equal 1? void function() { ... }

1) a[3] = 23;
2) a[1] = 1;
3) a[5] = 1;
4) a[5] = 6;
5) a[10] = 5

Dean wants a quick way to look up staff members by their staff id. in cell q3, nest the existing vlookup function in an iferror function. if the vlookup function returns an error result, the text “invalid staff id” should be displayed by the formula. (hint: you can test that this formula is working by changing the value in cell q2 to 0, but remember to set the value of cell q2 back to 1036 when the testing is complete.)

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?

Mariah was working on a multimedia presentation that included both video and audio files. the file was huge, and she wanted to send it to her coworker in another office. she needed to reduce the size of the file so that it could be transmitted faster. the utility she used to do this was