Questions

A posted speed limit of 55 mph means that we can drive at a speed of 55 miles per hour(mph) under good conditions in that area. We cannot that speed limit in that area.

In economics, the cost of something is what you give up to get it.

Gregarious is spelt correctly which means sociable.

To achieve maximum efficiency and reliability a mode of operation known as symmetric multiprocessing is used. In essence, with SMP any process or threads can be assigned to any processor.

Virtual memory is hardware technique where the system appears to have more memory that it actually does. This is done by time-sharing, the physical memory and storage parts of the memory one disk when they are not actively being used.

C.P. of 10 note books ⇒ 140 × 10 = 1400 Rs.
Profit on selling one pen ⇒ 50×200/100 = Rs 100
Number of pen required ⇒ 1400/100 = 14

The Mirror can turn everything around without moving.

Single selled organisms are also known as Unicellular organisms in which they have only one cell.

Examples are :: Fungi, Algae, Amaeba, Paramaecium,...

Hence, all the above given options are single selled organisms.