Answer:
Tyrannosaurus de la reconquista de la reconquista 
 
        
             
        
        
        
This question is flawed. I believe it was meant to ask: "If you ask a random person <span>who identifies as American</span> this question, what is the probability?" etc. Assuming this is the case, it would be 93% probability.
Otherwise, America is equivalent to 4.34% of the total world population as of Thursday, April 6, 2017 (http://www.worldometers.info/world-population/us-population/). So, 7% of 4.34% is 0.3%.
I'd stick to 93%
        
             
        
        
        
Answer:
quantity a is halfed
Corrected question;
A quantity a varies inversely as a quantity b, if, when b changes a changes in the inverse ratio. What happens to the quantity a if the quantity b doubles?
Step-by-step explanation:
Analysing the question;
A quantity a varies inversely as a quantity b, 
a ∝ 1/b
a = k/b ......1
when b changes a changes in the inverse ratio;
Since the change at the same ratio but inversely, k = 1
So, equation 1 becomes;
a = 1/b
If the quantity b doubles, 
ab = 1
a1b1 = a2b2
When b doubles, b2 = 2b1
a1b1 = a2(2b1)
Making a2 the subject of formula;
a2 = a1b1/(2b1)
a2 = a1/2
Therefore, when b doubles, a will be divided by 2, that means a is halfed.
 
        
             
        
        
        
The equation for that line is y=x+5