In the \( 4 \times 4 \) array shown below, each cell of the first three columns has either a cross (X) or a number, as per the given rule.
A number equals the count of crosses in its 8 neighboring cells (left, right, top, bottom, and diagonals). The fourth column is empty. As per this rule, the maximum number of crosses possible in the empty column is
Step 1: Analyze each row to determine the possible placement of crosses in the empty column.
Step 2: Evaluate the first row where the number \(2\) in the third column suggests two adjacent crosses. As there is already one cross in the third row, only one more cross can be placed.
Step 3: In the second row, the number \(3\) in the third column indicates that it is already satisfied by existing crosses. Hence, no additional crosses can be placed in the empty column.
Step 4: In the fourth row, the number \(2\) suggests that two crosses can exist in adjacent cells. Since the previous columns are satisfied, the empty column can accommodate a cross.
Conclusion: Based on the above observations, the maximum number of crosses possible in the empty column is 2.
Eight students (P, Q, R, S, T, U, V, and W) are playing musical chairs. The figure indicates their order of position at the start of the game. They play the game by moving forward in a circle in the clockwise direction.
After the 1st round, the 4th student behind P leaves the game.
After the 2nd round, the 5th student behind Q leaves the game.
After the 3rd round, the 3rd student behind V leaves the game.
After the 4th round, the 4th student behind U leaves the game.
Who all are left in the game after the 4th round?

The 12 musical notes are given as \( C, C^\#, D, D^\#, E, F, F^\#, G, G^\#, A, A^\#, B \). Frequency of each note is \( \sqrt[12]{2} \) times the frequency of the previous note. If the frequency of the note C is 130.8 Hz, then the ratio of frequencies of notes F# and C is:
Shown on the left is a set of equations. Which option belongs to the same set? 
Two soils of permeabilities \( k_1 \) and \( k_2 \) are placed in a horizontal flow apparatus, as shown in the figure. For Soil 1, \( L_1 = 50 \, {cm} \), and \( k_1 = 0.055 \, {cm/s} \); for Soil 2, \( L_2 = 30 \, {cm} \), and \( k_2 = 0.035 \, {cm/s} \). The cross-sectional area of the horizontal pipe is 100 cm², and the head difference (\( \Delta h \)) is 150 cm. The discharge (in cm³/s) through the soils is ........ (rounded off to 2 decimal places).

The most suitable test for measuring the permeability of clayey soils in the laboratory is ___________.
Consider the beam ACDEB given in the figure. Which of the following statements is/are correct:

For the beam and loading shown in the figure, the second derivative of the deflection curve of the beam at the mid-point of AC is given by \( \frac{\alpha M_0}{8EI} \). The value of \( \alpha \) is ........ (rounded off to the nearest integer).
