2 units
it has just moved, not changed lengths
Note that there's a strict order here -> 2 close friends, then 1 non-close friend.
So, picking in order:
probability of picking the first close friend: 4/10
probability of picking the second close friend: 3/9
probability of picking the first non-close friend: 6/8
So, we get 4/10 * 3/9 * 6/8 = 1/10.
Answer:
B
Step-by-step explanation:
Becasue you dont need too much.