A system contains $10$ units of resource of same type. The resource requirement and current allocation of these resources for three processes $\text{P, Q}$ and $\text{R}$ are as follows $:$
$\begin{array}{|l|l|l|l|}\hline & \text{P} & \text{Q} & \text{R} \\\hline \text{Maximum requirement} & \text{8} & \text{7} & \text{5} \\\hline \text{Current allocation} & \text{4} & \text{1} & \text{3} \\\hline\end{array}$
Now, consider the following resource requests:
- $\text{P}$ makes a request for $2$ resource units
- $\text{Q}$ makes request for $2$ resource units
- $\text{R}$ makes a request for $2$ resource units
For a safe state, which of the following options must be satisfied?
- Only request $\text{i}$
- Only request $\text{ii}$
- Only request $\text{iii}$
- Request $\text{i}$ and $\text{ii}$