Premier Paints Limited is preparing a budget for the next quarter of $2021$ but is uncertain of the level of activity that will enhance its performance for the year. The company provides the following information and request from you as a Cost Accountant to prepare estimates showing cost per unit for each of the following monthly levels of activity: $400$ units, $700$ units, $800$ units and $900$ units: $1.$ Materials: The company usually obtains required materials for a quarter at the beginning of the period. This is to take advantage of discounts and to prevent shortage of materials. If the company purchases $60,000$kg$,$ a discount of $10\%$ on normal price of N$500$ per kilogram will be obtained. $2.$ Labour: the company currently has $10$ operators and $2$ supervisors who are paid at the rate of N$600$ per hour and N$800$ per hour, respectively. All employees work for $54$ hours per week, $6$ days per week and receive overtime of one and half times normal rate of pay if they are required to work for more than $60$ hours per week. $3.$ Machine hours: The company produces a single product on $2$ machines, each of which requires $5$ operators and $1$ supervisor. Each machine costs N$7,000$ per hour to run. $4.$ Overheads cost: Factory overheads are fixed at N$500,000$ per month up to $750$ units aftem which they are raised by N$250,000$ per month. $5.$ Each unit of the product requires one$-$half machine hour and $30$kg of materials.