What measures the actual time that a processor spends working on a task?

In order to add and join tables in a select query, depending on how a table is created, the primary key fields:

A) must be defined. B) may or may not be defined. C) must be defined as a single field primary key. D) must not be defined.

The term used to describe a socket that requires no pressure on the CPU to install?

A. PGA B. LGA C. ZIF D. PIF