The answer is 12+3r because 4 times 3=12 then the 3r which you cannot add because they are no others variables that are r
<h3>
Answer: 21600 </h3>
==========================================================
Explanation:
There are 6 letters to pick from {A,B,C,D,E,F} and we have two slots to fill, where no repeats are allowed. This means we have 6*5 = 30 different ways to pick two letters.
There are 10 digits to pick from {0,1,2,...,9} and there are 3 slots to fill. This gives 10*9*8 = 720 different permutations for this portion.
Overall, we have 30*720 = 21600 different serial numbers possible.
No, Yes, No, Yes
using the laws of exponents
(1)
(
)³ = 
4³ × 4³ = 
≠ → No
(2)
(
)^4 = 
× = → Yes
(3)
= (6 × 3 )^8 = 
× ≠ 
× → No
(4)
= (4 × 5 )³ = 4³ × 5³ → Yes
K= 52!!
hoped this helped .
