Study the following line chart carefully and answer the questions given below:
Below the pair of five trains are given. The sum of length of each pair and the time taken by trains in each pair to cross each other when travelling in opposite direction is given in the line graph.
Length (in decameter) and Time (in sec.) taken to cross each other when travelling to opposite direction. (1 decameter = 10 meter)
To find the time taken by train B and train D to cross each other when they are traveling in opposite directions, we need to examine the line chart given in the problem. The line chart provides the sum of the lengths of each pair of trains and the time taken by these trains to cross each other. Below is a step-by-step solution to solve the problem:
Step 1: Understand the Measurement and Units
Step 2: Information Extraction from the Line Graph
Step 3: Calculate the Required Time
Conclusion
The approximate time taken for train B and train D to cross each other when traveling in opposite directions is \(9.78\) seconds, as per the line chart data provided.
Note: Confirm by checking the line graph to ensure the interpretation of the graph data aligns with the problem's given correct answer.
Contours in the bivariate (weight, height) graph connect regions of approximately equal popula-tions. Which of the following interpretations is correct?
The function $f(x)$ is plotted against $x$ as shown. Extrapolate and find the value of the function at $x = -1$.

Which of the following inferences can be drawn from the above graph?
Number of times a research paper is viewed and cited is shown in the plot. In which month was the percentage increase in citation more than the double of the percentage increase in view?

| Students | A | B |
|---|---|---|
| $S_1$ | 12 | 28 |
| $S_2$ | 10 | 29 |
| $S_3$ | 16 | 27 |
| $S_4$ | 05 | 29 |