The procedure for buying goods through mail order includes the following steps:
1. Catalog Selection: The buyer selects products from a catalog or online store.
2. Order Placement: The buyer places an order by filling out a form or placing an online request.
3. Payment: Payment is made in advance or upon delivery through cash, cheque, or online payment methods.
4. Order Processing: The seller processes the order and prepares the goods for dispatch.
5. Delivery: The goods are delivered to the buyer through postal or courier services.
Example: Buying books from an online retailer like Amazon follows a similar mail-order process.
| Case No. | Lens | Focal Length | Object Distance |
|---|---|---|---|
| 1 | \(A\) | 50 cm | 25 cm |
| 2 | B | 20 cm | 60 cm |
| 3 | C | 15 cm | 30 cm |