Answer #10 on page 21:

=2⋅10⁵/ 5⋅10² ⋅ 1/10²= should be

=2⋅10⁵/ 5⋅10⁻² ⋅ 1/10²=

Am I correct?

Nice catch, mrgimli - the answer choice (D, 40,000) is still correct, but it appears that we omitted that negative sign in the exponent in the denominator. My apologies for that - I can't recall if I wrote that question personally, but I wrote much of that book and can say that typing and double-checking all of the exponents in superscript was one of the more painstakingly tedious tasks of my life! I think we did pretty well overall, and we certainly appreciate your help in catching this error.