The symbols O, *, $\Delta$ , and $\square$ are to be filled, one in each box, as shown below. The rules for filling in the four symbols are as follows. Which symbol will occupy the box marked with '?' in the partially filled figure?
1) Every row and every column must contain each of the four symbols.
2) Every 2$\times$2 square delineated by bold lines must contain each of the four symbols. 
To solve the problem, we need to ensure that all rules of filling the symbols are followed:
Let’s analyze the partially filled figure:

Our task is to determine which symbol will fill the position marked with ?.
Considering the missing symbols and given constraints, the only symbol that fulfills all conditions (one of which must be a *) for the box marked ? is *.
Therefore, the symbol that correctly occupies the box marked with ? is *.
In the 4 x 4 array shown below, each cell of the first three rows has either a cross (X) or a number.
| 1 | X | 4 | 3 |
| X | 5 | 5 | 4 |
| 3 | X | 6 | X |
The number in a cell represents the count of the immediate neighboring cells (left, right, top, bottom, diagonals) NOT having a cross (X). Given that the last row has no crosses (X), the sum of the four numbers to be filled in the last row is
| TEAM 1 | TEAM 2 | |
| MATCH 1 | P and X | Q and R |
| MATCH 2 | P and R | X and Y |
| MATCH 3 | R and X | Q and Y |
Students applying for hostel rooms are allotted rooms in order of seniority. Students already staying in a room will move if they get a room in their preferred list. Preferences of lower ranked applicants are ignored during allocation.
Given the data below, which room will Ajit stay in?
| Names | Student seniority | Current room | Room preference list |
| Amar | 1 | P | R, S, Q |
| Akbar | 2 | None | R, S |
| Anthony | 3 | Q | P |
| Ajit | 4 | S | Q, P, R |