Textbook question E31 and E33

[Lorraine Jiang 2C]

Hello! I know these two questions are not included in homework but I was doing them for extra practice and I couldn't get the correct answer.

For E31, I got the mass of water which is 1.6kg, but I couldn't find the cost of it.
If anyone can help with these two questions I would really appreciate it!

[Olivia Smith 2E]

You would be paying $112 dollars for water. Just divide the mass of the water by the total mass then multiple that by the total cost. A fairer price would be $63! Hope this helps!

[Olivia Smith 2E]

For question 33, I just calculated the molar mass of both compounds with hydroxyapatite being 503.354 g/mol and fluorapatite being 505.307 g/mol. Then I just calculated the percentage difference which is 0.39%

[Lorraine Jiang 2C]

Ok I got it! Thank you so much!