Need some more info, what are the dimensions of the bricks?
        
             
        
        
        
"Bias" means someone shows inclination towards someone or something because of the relationship that person has with that thing or person. 
In this case, since Janine has friends that are also in the dance club, they are more likely to vote for her as president because they are friends with her. So, answer A is likely to be biased because the five people sampled are her friends. 
Answer C is also biased because the sample chosen already plan on voting for her as president, and they are more than likely to find others who plan to vote for her.
        
                    
             
        
        
        
Answer: 2343 / 256
Explanation
I will do this for you in two forms: 1) adding each term, and 2) using the general formula for the sum of geometric series.
1) Adding the terms:
 4
∑ 3 (3/4)^i = 3 (3/4)^0 + 3 (3/4)^1 + 3 (3/4)^2 + 3 (3/4)^3 + 3 (3/4)^4
i=0
= 3 + 9/4 + 27/16 + 81/64 + 243/256 = [256*3 + 27*16 + 64*9 + 4*81 + 243] / 256 =
= 2343 / 256
2) Using the formula:
n-1
∑ A (r^i) = A [1 - r^(n) ] / [ 1 - r]
i=0
Here n - 1 = 4 => n = 5
r = 3/4
A = 3
Therefore the sum is 3 [ 1 - (3/4)^5 ] / [ 1 - (3/4) ] =
= 3 [ 1 - (3^5) / (4^5) ] / [ 1/4 ] = 3 { [ (4^5) - (3^5) ] / (4^5) } / {1/4} = 
= (3 * 781) / (4^5) / (1/4) =  3 * 781 / (4^4) = 2343 / 256
So, no doubt, the answer is 2343 / 256
        
             
        
        
        
Answer:
Dividing a power of 4 by 4 is equivalent to ( reducing,) the exponent by (1).
Step-by-step explanation:
Let the power of 4 be 3
4 *4*4
We divide by 4
4*4*4/4 = 4*4 = 4^2
So we removed 1 power
Notice that 3-1 =2
Let 4 be raised to any power
4^a
We divide by 4
4^a/4  we remove 1 of the powers
we are left with
4^(a-1)
So we reduce the exponent by 1
 
        
                    
             
        
        
        
It is going to be a right triangle