What unique key is known only by the system and the person with whom the key is associated?

Public key is the key known by the system and the person associated with the key.

Explanation:

The other type of key called Private/Secret key is known only to the person who owns the key.

some have built technology like spoofed call blockers into their networks, so there's nothing you would even have to install.

this happens because the number is known for scamming, they don't want it to me known as "scam likely." perhaps it's just a telemarketer. maybe it's an identity thief. it might even be a scam artist.  

either way, "scam likely" is probably not an old friend whose number you forgot that you saved. it's your wireless carrier's way of letting you know: answer at your own risk.

explanation:

to combat the seemingly rising epidemic of spam callers in the u.s., the nation's four major wireless carriers have been trying out new methods to reduce the number of unsolicited calls americans receive each day.

some have built technology like spoofed call blockers into their networks, so there's nothing you would even have to install.

hope this . mark me brainliest.

can you include the statments that complete the question ?