Database Administration Questions

Given total number of students in the class = 21

So each student will have 20 greeting cards to be send or receive (21 - 1(himself))

Therefore, the total number of greeting cards exchanged by the students = 20 x 21 = 420.

Light travels Faster than Sound.

Light :

1. Light doesn't require a medium to travel.

2. It travels in the vaccum with the speed of 1,86,000 miles per second.

Sound:

1. Sound rquire a medium.

2. It travels in the Air with the speed of 340 meters per second.

3. It travels Faster in Water than in Air.

4. It travels Faster in Steel than in Water. 

When writing Node.js applications, ending up with hundreds or even thousands of dependencies can easily happen.
For example, if you depend on Express, you depend on 27 other modules directly, and of course on those dependencies' as well, so manually checking all of them is not an option!

The only option is to automate the update / security audit of your dependencies. For that there are free and paid options:

1. npm outdated
2. Trace by RisingStack
3. NSP
4. GreenKeeper
5. Snyk

Michael Faraday invented Electric Generator in 1831.

• The operating principle of electromagnetic generators was discovered in the years of 1831–1832 by Michael Faraday.

• The principle later called Faraday's law, is that an electromotive force is generated in an electrical conductor which encircles a varying magnetic flux.

We have 12 months.

In every month we get 28 or more days. 

So that implies we get 28 days in each and every month.

A Sandal.

It has sticking strips to make them fit for our feet. If you bind them only you can start walking or other wise it comes out.

In latest generation computers, the instructions are executed both sequencially and parallelly.

The ratio of money she lended is

24000 : 16000 = 3 : 2

Let the rate of interest be R%

8%                   R%
     

           10

3          :           2

R = 13%.