Joseph Henry in about 1835. He is American and he made something called a relay.
The answer is a) It improves upon the two-phased commit by requiring that locks be acquired at the start of a transaction.
Reason: The 3PC is an extension or you can say developed from 2PC that avoids blocking of an operation. It just ensures that first n sites have intended to commit a transaction that means it acquires commits or locks before the start of any transaction to avoid any blocking.
Option b) is wrong as it does not allow coordination, it just let all the other sites do their transaction if any other site is blocked, so no coordination is there between sites that they will wait till their coordinator is corrected.
Option c) is wrong as lock operations are shared between other connections as when their coordinator fails, the new coordinator agrees to the old coordinator that they had shared locks before and they can start their transaction.
Option d) is wrong as option a) is correct.
If you like the answer, please upvote.
Answer:
Option A is correct
Digital Subscriber line is a way where telephone companies provide internet access for connection.
It is a communication medium used to transfer digital signals. DSL is one of the most popular broadband internet access.
Explanation:
DSL stands for Digital Subscriber Line. DSL works with high-speed bandwidth that connects from a phone jack to a telephone network. DSL works within frequencies. You can use the DSL while making phone calls.
The phase where developers identify the particular features and functions of a new system is the requirement and analysis stage.
<h3>What is system development?</h3>
System development is the process of defining, designing, testing, and implementing a new software application or program.
System development has a life cycle. The primary stages are as follows;
- Operation and maintenance.
Therefore, the phase where developers identify the particular features and functions of a new system is the requirement and analysis stage.
learn more on system development here: brainly.com/question/13042526
#SPJ12
In applying for a license, students must take the knowledge test online or in the licensing office. However, the exams do not stop there, they also need to test the skills test or a drive test after passing the knowledge test. This is to complete their application for a driver's license.
