$2.$ The probability distribution of the monthly sales of an item is as follows:Daily Sales $($units$)$ O$-$NProbability$0\mathrm{.}060\mathrm{.}010\mathrm{.}060\mathrm{.}250\mathrm{.}300\mathrm{.}220\mathrm{.}10\mathrm{.}06$The cost of carrying inventory $($unsold during the day$)$ is Rs$.30$ per unit per day and the cost of unit shortage is Rs$.70.$ Determine the optimum stock to minimize the expected cost and also calculate EVPI.