Questions

The DSM is the Diagnostic and Statistical Manual of Mental Disorders. Its primary pupose is to help the mental health professionals like psychiartists, psycologists, etc... to treat mental illnesses. The DSM is published by the APA, American Psychiatric Association.

Let the two digits be x & y

From given data in the question, we get

x + y = 3(x - y)

x + y = 3x - 3y

=> 2x = 4y

x/y = 2/1

For having the 2:1, numbers satisfying are

12, 21, 24, 42, 36, 63, 48, 84

From this 36 is eleminated because it is a perfect square and no others are prime or perfect squares.

Hence, there exists 7 such 2-digit numbers => 12, 21, 24, 42, 63, 48, 84.

In the history, Rurik was believed to be the first ruler to consolidate the slavic tribes. He was a Russian leader in the 9th century.

The himalayas are the range of mountains that stretch upto 1500 miles in the southern asia in between India and China. 

Himalayas redirect monsoon winds south and southeast asia.

The first ever joint military exercise named 'Sagarmatha Friendship-2017' is all set between Nepal and China. Sagarmatha is the Nepali name for Mt Everest, which stands in between both the countries.