A double bar graph is a graphical display of information using two bars beside each other at various heights.

The bars can be arranged vertically or horizontally.

We can use a double bar graph to compare two data groups. A double bar graph has two axes.

So, here a double bar graph can be used, one set of graphs for each of the 2 days.

5 students uses bus

3 students uses bike

1 student uses taxi

2 students uses train

6 students uses car

5 students walk to school

Total number of students = 5 + 1 + 3 + 2 + 6 +5 = 22

The given data are grouped into classes. Hence the graph that should be used to represent them is histogram.

6 of them favored blue and 3 favored pink.

6 − 3 = 3 .

Therefore 3 more favored blue than pink.

The graph is as shown above. From the graph, it can be observed that the points do not form a straight line. It can be seen that the temperature is the highest on day 6.

We can see this example as a type of pie chart. The medium pizza is a small pie chart, which is divided into 8 equal parts. So, the percentage of pizza eaten by you is $\frac{1}{8}$x100. Similarly, in the large pizza a similar pie chart is depicted. This is again divided into 8 equal parts, the percentage of large pizza eaten by you is  $\frac{1}{8}$x100. So, the percentage of large pizza eaten by you will be same as percentage of medium pizza eaten by you. 

From graph it can be seen that number of people in the store is highest at 1 pm.

After plotting point A, B and C on the graph. We will get a straight line.

Line graph can represent data that continuously changes with time because a line graph is such that for each and every value of time, a value of the datum can be obtained. For example, if my temperature is continuously changing with time, using a line graph my temperature at any time can be shown.

x-coordinate is the distance of point from y-axis and y-coordinate is the distance of point from x-axis. Since, y-coordinate is 0, the distance of point from x-axis will be zero which means the point will lie on x-axis.