Lets see, database contains a large portion of information in one area. While you can edit and send information. These are generally used to organize the data inside.
Answer:
Option (d) is correct.
Explanation:
In java language "ar.length" is used to tells the size of the array. The array is used to declare more than one variable. Its index value is started from 0. so when a user needs to initialize the value of an array, they need to start the index value at 0. because ar[0] indicates the first variable of an array.
In option (d), index value is started from 0 and ends with (array_size-1). so it gives the accessed to all the variable of an array and the statement "ar[i]=4;", initialize the value 4 to all array variable.
while another option is not valid because--
- In option a, Index value starts from 1 which accesses the second variable of an array.
- In option b, the statement "i<= ar.length;", gives an unbound array exception because it took the size greater than the array size.
- In option c, statement "i<ar.length-1;", can not give accessed to the last element of an array.
Answer:
24.167 micro seconds.
Explanation:
The given rotation rate = 7200 rpm = 7200 rounds per minute
Rotational latency is the average time taken for the head to reach starting of sector
.
Rotational latency (in micro seconds) = (1 / (RPM / 60)) * 0.5 * 1000
(1/(7200/60))* 0.5 * 1000 = 4.167 ms
Thus, rotational latency = 4.167 ms.
Seek time = 20 ms
The average time taken for the access head to get to the beginning of randomly selected sector will be equal to the average time to first reach the random track plus the average time taken to reach random sector
.
= 20 ms + 4.167 ms = 24.167 micro seconds.
Thus, it would take 24.167 micro seconds to get the access head to the beginning of a randomly selected sector on a randomly selected track.
Name at least four alternative devices that can be used as sources of alphanumeric character input data.
1- Optical character recognition, 2- Bar code reader, 3-Magnetic stripe readers, 4- RFID input, 5- Voice input.
