These files appear here is the same order as they appear in the zyBook.
Note: PA=Participation Activityi and CA=Challenge Activity.

CountDownTimer.java is based on PA 14.2.1.
RecursiveCalls.java is based on CA 14.2.1.
NumberGuessGame.java is based on Figure 14.3.1 and PA 14.3.2.
NameFinder.java is based on Figure 14.3.2.
NumberSearch.java is based on CA 14.3.1.
NameFinderWithError.java is based on Figure 14.4.1 and zyDE 14.4.1.
PrimeChecker.java is based on zyDE 14.5.1.
CalculatePennies.java is based on CA 14.5.1.
RecursivelyPrintFactorial.java is based on CA 14.5.2.
FibonacciSequence.java is based on Figure 14.6.1.
FibonacciSequenceF_N.java is based on zyDE 14.6.1.
GCDCalc.java is based on Figure 14.6.2.
ExponentMethod.java is based on CA 14.6.1.
WordScrambler.java is based on Figure 14.7.1.
ShoppingSpreeCombinations.java + GroceryItem.java are based on Figure 14.7.2. 
TravelingSalesmanPaths.java is based on Figure 14.7.3.
NumScrambler.java is based on CA 14.7.1.
StackOverflow.java is based on PA 14.8.1.
PermutationsSolution.java is based on zyDE 14.9.1 and zyDE 14.9.2.