You can define a cell site as a single site that has a cell phone traffic through the single site. You can find this information online in encyclopedias such as Wikipedia.

it occurs in three stages.

stage 1:in this it(current cell site) searches for the new cell site near to it(not allocated channel).

stage2:in this it confirms whether a cell site is ready for hand off.

stage3:in this the hand off occurs.

if it does not get any response from the cell site(in stage 2) which it is looking for then it prefers for another,if no cell site is ready for hand off,the signal will be continued by the current cell site till the stage3 and later the signal is lost.

The primary site for blood cell production is the bone marrow.

is there a site that gives celebs cell number?

It depends on your phone,the cell site,the switching station, the cell site of the receiver and the receivers phone