<span>In general you want to use the cheapest storage medium who's speed is compatible with the function it needs to perform. For active storage that's handled while running programs, you need memory whose speed is closely matched to the processor speed. And that would be the rather expensive semiconductor memory which is close to ideal for the task. But semiconductor memory has the disadvantage of being expensive and it loses the values stored when power is lost. So slower, persistent storage is used such as SSD (Solid State Drives) and hard disks. That media is cheaper, but slower, but still fast enough to handle tasks such as loading programs and data into memory for execution, or storing data generated by programs to persistent storage. But as with all man made things, disasters happen. Computers break down, hard disks crash, floods and fires happen, etc., and as a result data is lost. So we make backups. Backups have to have a lot of storage and they have to be cheap. But they don't need rapid access, you can start at the beginning and read (or write) all the way to the end. And for that purpose, magnetic tape is ideal. Magnetic tape is actually quite fast when you're simply streaming a continuous stream of data without any need to randomly access any piece of that data. And it's cheap, so you're willing to make a back up copy of your system and store that backup off site so a single disaster won't destroy both the primary system and the backup.</span>
Answer:
Sir William Crookes invented the cathode ray tube in 1878, but these discoveries took many years to merge into the common ground of television. His mechanical system used a scanning disk with small holes to pick up image fragments and imprint them on a light-sensitive selenium tube. A receiver reassembled the picture.
Answer:
The value of the following expression is "2".
Explanation:
Here x has value 2 means x=2,and y has value 2 means y=2.
so (x+3)/(4-y)
(2+3)/(4-2)
5/2 it gives 2 because /(slash) operator gives the quotient part .The slash operator divide the left hand operand by the right hand operand.On dividing 5/2 it returns integer value i.e 2.
Hard to see, if you make it normal size I might b able to help
