Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to engrave stone [title] Find a stone. [step] Your skill level and the design you want to create will determine the type of stone you need. [substeps] Stones with a flat surface, such as river rocks, work best for beginners.

Ending1: Typically, beginners work with stone buildings, especially those located near rivers and banks. Large structures, such as brick or masonry, require fluxes to work with. Ending2: Softer sedimentary rocks (such as sandstone, limestone and soapstone) are easier to drill into. Keep your eyes open for stones when you're outside at the beach, in your garden, etc, or purchase engraving stones from your local arts and crafts store. Ending3: [title] Select a stone with full or partial drainage. [step] Stones with drainage are the easiest to craft. Ending4: Stones with sharp edges and a hilling point result more powerful or more valuable but if a stone jumps or falls over or provides a severe dent, the stone will probably opt for a harder stone. However, stones with low levels of oxidation and silicone are more likely to chip over time.

Answer format: ending1/ending2/ending3/ending4