There is no equivalence.
A quart is a measure of volume. 9x9 is a non-specific measure of area. The two measure different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid without some addition information.
The casserole measure is non-specific because the question does not specify whether it is 9 in x 9 in, or 9 cm x 9 cm (unlikely) or 9 dm x 9 dm.
14 cups or 3.5 quarts. Here is a link to a very nice conversion chart for pans and casserole dishes: http://missvickie.com/resources/bakeware%20chart.htm
3 quarts - If you look in the bottom of the pan it is normally etched in stating how many quarts and Liters it will hold
the 9X13 holds 3 quarts
Pour 2 quarts of water into the 9 x 13 pan and you will see for yourself - that's what I always do if I'm not sure.
12 to 16 depending on how large you cut them...
about 5 and 1/2 quarts will fit in that pan
9 quarts + 9 pints = 13 quarts 1 pint
17 quarts
9 fluid ounces is about 0.28 quarts.
9 pints is 4.5 quarts.
approximately 2 quarts.
1 gallon = 4 quarts 9 quarts = 2.25 gallons
There are 4 quarts in a gallon. Therefore, 9 gallons is equal to 9 x 4 = 36 quarts.