Permutations are all possible variations, in which a set of numbers or characters can be ordered. <span>The number of permutations on a set of </span><span> n elements is given by </span><span> n!. </span>In our case we have 9 digits, which means 9 elements.
There are 9!=9*8*7*6*5*4*3*2*1=362880 possible variations, or 362880 possible identification numbers.
I also posted this answer on your previous question
Answer:
That is the commutative property.
The answer is (y - 4)2 = -12(x - 2)
Since the graph is facing the left, the starting equation would be (y - k)2 = -4p(x - h).
(h, k) is the vertex of the graph. If you plot the focus and the directrix, you can see that the distance is 6. Divide 6 by 2, thus the vertex should be 3 squares away from the focus and 3 squares away from the directrix. The vertex is (2, 4). And since the distance from the focus to the vertex and the distance from the directrix to the vertex is 3, P = 3.
Insert the numbers in and you should get the last choice.
