A histogram is drawn for discrete data.

The table shows a frequency distribution of the life times of $400$ radio tubes tested at a company. With reference to this table determine the 

Upper limit of the fifth class is?

The table shows a frequency distribution of the life times of $400$ radio tubes tested at a company. Determine the lower limit of the eighth class.

The histogram below shows the weights of $\mathrm{}72$ newborn babies:

Find the ratio of the number of babies weighing $5 \mathrm{kg}$ or more but less than $6 \mathrm{kg}$, to the number of babies weighing $3 \mathrm{kg}$ or more but less than $4 \mathrm{kg}$.

Find the class interval of $0-\mathrm{5,5}-\mathrm{10,10}-\mathrm{15,15}-20.$

* The question given in the textbook is Incorrect, so the modified question is as follow

Find the size of the class intervals :$0-5,5-10,10-15,15-20.$

The number of hours for which students of a particular class watched television during holidays is shown through the given graph.

If the maximum number of students watch the TV for $a-b \mathrm{hours}$, then find the value of $a+b.$

Look at the given below data.

$$\begin{gathered} 39, 25, 5, 33, 19, 21,12, 48,13, \\ 21, 9, 1, 10, 8, 12, 17, 41, 40, \\ 12, 46, 37, 17, 27, 30, 6, 2, 23,19 \end{gathered}$$

The frequency distribution of the data is given here.

Which of the above tables is the frequency table of the given data?