That would be radar.
This was a key battle between Britain's RAF (Royal Air Force) and the Luftwaffe, if the Germans would've won most likely Britain would've been German; and many different outcomes could've happened in the past.
But, since radar was invented, and the British employed it in their tactics; that along with the communication between them helped repel the attack in the Battle of Britain.
It gained political and security benefits.
Employers locker workers in or out of the workplace.
Answer: the number of residents has grown substantially
Explanation:
