A Very Light Wire Is Used to Hang a Series

Short Answer

A very light wire is used to hang a series of 8.0-kg bricks.This wire will break if it exerts a force on an object greater than 450 N.The bricks are hung one below the other from a hook in the ceiling using this wire,as shown in the figure.
(a)How many whole bricks can be hung without breaking the wire?
(b)If you add one more brick to the number found in part (a),which string will break?