The figure depicts a transportation problem along with the solution. The correct statement is

For the conveyor belt drive shown, the tension on the tight side $(T_1)$ is double that of the slack side. The coefficient of friction between belt and drum is 0.21. The minimum angle of lap (in degree) to avoid slippage of the belt is ______.

The operational status of an HEMM in a shift is shown in the diagram. The availability of the machine in % is ______.

Match the following blasting elements with the corresponding initiators.

The feasible region of a linear programming problem is shown in the figure. The maximum value of the objective function $Z = 4X + 3Y$ is ______.

Cash flow of a project of duration 4 years is shown. The uniform income ‘R’, in Rs. crores, at the end of 2$^{nd}$, 3$^{rd}$ and 4$^{th}$ years for an internal rate of return of 10% is ______.

A rectangular field of area 20000 m$^2$ is to be divided into 6 different plots by fencing as shown in the figure. The value of L in m for which the total length of fencing becomes minimum is ______.

For the ventilation system shown, the combined resistance of the trunk airways and the shafts is 2.2 Ns$^2$m$^{-8}$. The resistances of splits A and B are 0.5 Ns$^2$m$^{-8}$ and 0.8 Ns$^2$m$^{-8}$ respectively. A regulator of size 2.0 m$^2$ is placed in split A. Considering the fan generates a pressure of 1000 Pa, the air flow in m$^3$/s in split B is ______.

A mine air sample contains CH$_4$, CO, H$_2$, N$_2$ and O$_2$. The mine air analysis using Haldane apparatus gives the following results expressed in percentage of total sample volume.

Total contraction after combustion : 10.0

CO$_2$ formed after combustion : 6.0

O$_2$ consumed in combustion : 9.5

The percentage of CH$_4$ in the sample analysed is ______.

Out of the support categories given for an underground coal mine, identify the ‘active support’.