Which of the following graphs of $\log \, K \rightarrow 1/T$ can be used to calculate the activation energy?

For an endothermic reaction,the energy of activation is $E_a$ and the enthalpy of reaction is $\Delta H$ (both in $kJ/mol$). The minimum value of $E_a$ will be:

For a hypothetical reaction $A \to B$,the activation energies for forward and backward reactions are $19 \ kJ/mol$ and $9 \ kJ/mol$ respectively. The heat of reaction is $.... \ kJ$.

An increase in temperature by $10\,^{\circ}C$,generally increases the rate of a reaction by .......... times.

The graph for the process $R \rightarrow P$ is given below. Determine the activation energy $(E_a)$ for the forward reaction if the energy of the reactant is $50 \ kJ$ and the energy of the transition state is $170 \ kJ$. (in $kJ$)

Fill in the blank :
$1.$ In collision theory the molecules are hard .........
$2.$ In a reality the molecules are hard ..........
$3.$ Collision take place with .......... species.