Using the equation a-b=2, we can solve that a = 2+b.
We can then <u>substitute that into the expression</u> given to get 3^b/3^(2+b).
Since <u>they have the same base, we can subtract the exponents from the numerator and denominator</u> to get 3^(b-2-b) which <em>simplifies to 3^-2.</em>
<span>Apprentice B earns $120 because Apprentice A's wage is $4/hour (160 divided by 40), and the question states that they are paid at the same scale. Therefore 4 x 30 = $120.</span>