Questions

1) ability to support multiple processors
2) virtual storage
3) source level debugging

An up - selling is getting the customer to spend more money, buy a more expensive model of the same type of product, or add features or warranties that relate to the product viewed or purchased. 

A cross - sell is to get the customer to spend more money by adding more products from other categories than the product being viewed or purchased. 

The stability triangle is used to describe the movement of center of gravity of a load vehicle like trucks. If the load is not balanced then it moves and may tip over it.

If you were to raise a lift truck up and look at its underside, you would see that the support points for the truck are located at points A, B, and C. The triangle formed between points A, B, and C is called the Stability Triangle. The lift truck will not tip over as long as the center of gravity remains inside the triangle.

The center of gravity is the point within a lift truck where there is equal weight all around it.

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.

Computer is the correct word.

Let the required number be 'X'

Condition 1 :  

$$\begin{gathered} XX = 2X \\ => 2X2 = X \\ => X = 12 \end{gathered}$$

Condition 2 :

$$\begin{gathered} X × X = X2 \\ => X = 12 \end{gathered}$$

Therefore, 12 is the number which becomes double when it is divided by itself and becomes half when it is multiplied by itself.