Answer:
B and D
Step-by-step explanation:
I think this is the answer
The answer is 0
The formula is
n!/ r!(n-r)!
4!/ 9!(4-9)!
Answer:
8
Step-by-step explanation:
If the order matters it is a permutation. For example: if you are selecting 3 people to be on a committee it doesn't matter what order you select them, but if you're selecting three people to be president, vice president, and secretary the order in which you choose them matters the first person being president, the second person being vice president, and the third person be secretary
Answer:

Step-by-step explanation:
The magnitude of vector
is given by 
The magnitude of vector
is
.

The magnitude of vector
is
.

Therefore,
