Answer:C
Step-by-step explanation:45
Answer:
680
Step-by-step explanation:
Use the binomial coefficient where you choose
numbers out of
possible numbers and find the total amount of combinations since order does not matter:

Thus, you can make 680 three-non-repeating-number codes
Answer:
no
Step-by-step explanation:
4x +12 = 4
4(2) +12 =/= 4
8 +12 =/= 4
8 +12 = 20
(sorry if it doesn't make sense,I tried)
Answer:
17
Step-by-step explanation:
Answer:
Maybe they are all 13s th am sure