A company produces electric scooters for commercial application. The same company also produces rechargeable batteries for the electric scooters. The fixed cost for electric scooters production is RM200,000 per month. The fixed cost for rechargeable batteries is RM50,000 per month The variable cast per scooter is RM100. The variable cost for the rechargeable butteries is RM30. The selling price per unit both Scooter and its rechargeable batteries is p=1000-0.46D. ) 

a. Find optimal units for both scooter and its rechargeable battery.

b. For the optimal units, please prove if the optimal units produce profit or lass for the company.