The materials you could use to make DIY headphones are the following:
Headband - A headphone has a headband used to put over your head. You can use a normal headband for this.
Small Tin Cans - This can be used for the housing of the speaker.
Foam - The speaker has earpads. You can use foam for this.
Wire with jack - You can use a wire with a jack from an old broken earphone or headphone.
Speakers - This one is hardest and the most important part of the headphone. You can look up how to make one using magnets and copper wire or you can just recycle an old pair of working speakers that fit in tin can housing.
Answer:
Bluetooth
Explanation:
Bluetooth is a standard to share data between Mobil devises, typically less than 10 m (33 ft), up to 100 m (330 ft), but the Bluetooth 5.0 has a range of 40–400 m (100–1,000 ft), in addition, NFC is something similar because needs a separation of 10 cm or less, and with RFID we can read to hundreds of meters.
Explanation:
Here, in the given statement, maximum flow capacity of the ALOHA channel = 18.4% = 0.184
Then, the stations N share 56 kbps
And, the channel rate = 
Then, the outputs of the wach stations is 
, the output of the bits/ sec by each stations = 
So, The output of the N stations is 10 bits/sec on the channel that having 
Finally, N = 
Solution:
The installation wizards in most of the commercial Linux distributions provide an option to create a custom disk layout, specifying which the RAID arrays can be created and the root. Additional RAID arrays can be configured by using the mdadm
It is known as (Redundant Array of Independent Disks) is a data storage virtualization technology that combines multiple physical disk drive components into one or more logical units for the purposes of data redundancy, performance improvement.
Data is distributed across the drives in one of several ways, referred to as RAID levels, depending on the required level of redundancy and performance. It provide protection against unrecoverable sector read errors, as well as against failures of whole physical drives.
This is the required solution.
Cryptographic hash functions are utilized in order to keep data secured by providing three fundamental safety characteristics: pre-image resistance, second pre-image resistance, and collision resistance.
