Asecurity system uses sensors at every door and window which will set off an alarm if any one of them is opened. there is also a keypad by an entry door to turn on or turn off the system. describe how these components can be wired in a combinational circuit to provide the needed security.

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?

How is the number 372 written when expanded out to place values in the base 8 (octal) number system? a. 2 x 4 + 3 x 2 + 4 x 1 b. 3 x 64 + 7 x 8 + 2 x 1 c. 3 x 8 + 7 x 7 + 2 x 6 d. 3 x 100 + 7 x 10 + 2 x 1

Write a program that inserts the digits of an integer into an array in originalorderfollowed by reverse order. first, promptthe user to enter a positive integer(> 0). determine the number of digits of the integer. create a dynamically allocated integer arrayof a size twice the number of digits.now insert the digits in original order which will occupy half of the array. then, insert the digits in reverse order.finally, output thedigits in thearray.use at least two functions to organize your program.