Given conditions are :
In 1980's, a typical middle-income household earned= $34,757
In 2009, a similar middle-income household earned= $38,550
And we have to find relative increase in income for these households from 1980 to 2009.
So first we will find the total increase in amounts.

Relative increase = 
= 10.91% or rounding it off we get approx 11%.
Hence, the answer is 11%.
The range refers to the value of y for which x is define.
So let y=f(x),

Try making x the subject to obtain,

x is defined for all real values of y greater than
0.
Hence the correct answer is D.
Hi I hope you are all okay could someone help me with this math question thankyou !!!
y
∝
1
√
x
If
y
=
7
when
x
=
64
find,
x
when
y
=
8