We know the distance formula is

9)
Here A( -4,2) and B(1,4)
So length of AB
= 
Also C(2,1)
Length of BC
= 
So we can see that length of AB is not equal to length of BC
11.
Now AB = 
Also C(2,-1) & D(4,4)
Length of CD
= 
Yes AB = CD
You know that 3 times 2 is 6 so 30'times 20 equals 60
Answer:
4) Unbiased; 5) Biased
Step-by-step explanation:
4) states that the audience of the poll was "random" people meaning it's a good foundation of data as they weren't chosen for the employee noticing their specific affiliation with being overjoyed with the product (as the question doesn't say) or for not liking (have complaints about it) the product.
5) The audience of the poll is fans of a sports team--definitely biased because they'll say they love the 49ers being a fan for them. Leads to skewed results not representing a portion of a population accurately.
The survey sample includes residents of the neighboring city whose phone number is listed.
So this says
n*(-5/8)=-0.4
n(5/8)=0.4
n=0.4x8/5
n=16/25