Which of the following is not a factor affecting elasticity?
a - availability of substitutes
b - the good's relative importance
c - whether the good is a necessity or a luxury
d - gdp

Answerwinchell would use the residual method($120-$100)=$20;

The correct answer is:   6.99 billion (as 6.986 billion is rounded off (to nearest hundredth place)  to 6.99 billion)explanation: the given function is:   y = 6.2(1.01)^x (1)where x =    number of years after 2000it means that in 2012, the value of x would be 12 as the difference between 2012 and 2000 is 12 years.put x = 12 in equation (1): (1) => y =  6.2(1.01)^12 = 6.986 billion = 6.99 billion