(1) By analyzing the experimental data of the experimental serial number 1 or 2 or 3 in table 1 (4 or 5 or 6 in table 2) (7 or 8 or 9 in table 3), it is found that the lower the liquid density, the greater the depth.

(2) By analyzing and comparing the data of 1, 2, 3 in table 1 or 4, 5, 6 in table 2 or 7, 8, 9 in table 3, it is found that when the depth of the same liquid increases several times, the pressure is proportional to the depth;

(3) Xiaohua thinks that the pressure of the liquid at the bottom of the container is related to the gravity of the liquid in the container, so the pressure is the same and the depth should be the same, which is obtained from 1, 4,7 or 2,5,8 or 3,6,9 in the table. Although the pressure is the same, but the gravity of the liquid is different, it can be judged that Xiaohua's conclusion is wrong;

(4) In Figure A, the pressure of liquid on the bottom of the container is equal to gravity; In Figure B, the pressure of the liquid at the bottom of the container is less than the gravity of the liquid; In Figure C, the pressure of the liquid at the bottom of the container is greater than the gravity of the liquid. According to F=pS, the pressure is the same in several cases. Although the gravity of the liquid is different, the pressure of the liquid on the bottom of the container is equal because of the same bottom area. It can be concluded that the liquid pressure at the bottom of the container is equal to the ratio of the liquid pressure at the bottom of the container to the area at the bottom of the container.

So the answer is: (1) At the same pressure, the smaller the liquid density, the greater the depth; (2) 1 in table 1, 2,3 or 4,5,6 in table 2 or 7,8,9 in table 3; For the same liquid, the pressure is proportional to the depth of the liquid; (3) 1, 4,7 or 2,5,8 or 3,6,9; Mistakes; (4) The pressure of the liquid at the bottom of the container.