If the perimeter of figure formed by joining two regular pentagons of same size is $56 \mathrm{cm}$ and the length of each side is $k \mathrm{cm}$, then find the value of $k$.

What's the result, if place values of all the digits of decimal number $43.81$ are added$?$ 

Give one word or sentence for the following:

Express $8 \mathrm{km} 5 \mathrm{m}$ in $\mathrm{km}$ using decimals.

What is the coefficient of $a{b}^2$ in the expression $3a^{2}b-5a{b}^2+1$?

The number of prefects from different classes in a school is shown by the following pictograph:

Which class has the maximum number of prefects$?$ What is the number$?$

The number of perfects from different classes in a school is shown by the following pictograph.

What is the total number of prefects from $\mathrm{IX}$ to $\mathrm{Xll}$?

The number of prefects from different classes in a school is shown by the following pictograph:

Is it true that the number of prefects from class $\mathrm{IX}$to $\mathrm{Xl}$are more than the prefects from class $\mathrm{Xll}$? If yes, find by how much.