Z.ai: GLM 4.5 Air

The hardest **natural substance** on Earth is **diamond**. Here's a breakdown of why: 1. **Diamond's Hardness:** Diamond's hardness is measured on the **Mohs scale** of mineral hardness at **10**. This is the highest possible rating on this scale, meaning it can scratch any other mineral. It's also exceptionally hard on other scales like the **Vickers hardness test**. 2. **Structure:** Diamond is a form of pure carbon. Its incredible hardness comes from its unique crystal structure – each carbon atom is bonded to four others in an extremely rigid, tetrahedral arrangement (a strong covalent network lattice). This structure makes it incredibly resistant to scratching or deformation. 3. **Natural Occurrence:** Diamonds form naturally deep within the Earth's mantle under extreme heat and pressure over billions of years. They are brought to the surface by volcanic eruptions (kimberlite pipes) and are mined or found alluvially. **Important Considerations:** * **Lonsdaleite:** A theoretical form of carbon (like diamond but with a hexagonal crystal structure) formed under extreme shock pressure, like that found in meteorite impacts. **While laboratory studies suggest lonsdaleite *might* be slightly harder than diamond, naturally occurring, high-quality lonsdaleite crystals are incredibly rare.** Most natural "lonsdaleite" is found as intergrowths with diamond or has significant defects, making its actual hardness often comparable to or less than pure diamond. **Therefore, diamond remains the undisputed hardest *naturally occurring substance* that is readily available and well-characterized.** * **Hardness vs. Toughness:** Diamond is the *hardest* (resists scratching), but not necessarily the *toughest* (resists breaking or shattering). It can be brittle and cleave along specific planes if struck sharply. * **Synthetics:** Lab-created diamonds have the same hardness and structure as natural diamonds. Other synthetic materials like cubic boron nitride (CBN) or aggregated diamond nanorods (ADNRs) can be harder than diamond, but they are not *natural* substances. **Conclusion:** While rarer forms like lonsdaleite *might* theoretically surpass diamond's hardness under specific conditions, **diamond** is the hardest **natural substance** that is consistently found and measured on Earth. Its perfect covalent bond structure makes it the benchmark for hardness in the natural world.

The capital of Australia is **Canberra**. Here's a bit more context for clarity: * **Not Sydney or Melbourne:** While Sydney is the largest city and Melbourne was the temporary capital for a time, Canberra was purpose-built as the federal capital. * **Location:** It's located in the Australian Capital Territory (ACT), which is a separate enclave within New South Wales. * **Reason:** Canberra was chosen as a compromise between Sydney and Melbourne to end the rivalry between the two largest cities. It officially became the capital in 1927.

600Watts

Josh bought the house for $80,000 and spent $50,000 on repairs, resulting in a total cost of $80,000 + $50,000 = $130,000. The repairs increased the value of the house by 150%. Since the original value of the house was $80,000, the increase is calculated as: 150% of $80,000 = 1.5 × $80,000 = $120,000. The new value of the house after repairs is: Original value + Increase = $80,000 + $120,000 = $200,000. Assuming Josh sells the house at this new value, the profit is: Selling price - Total cost = $200,000 - $130,000 = $70,000. Alternatively, the profit can be found by subtracting the repair cost from the increase in value: Increase in value - Repair cost = $120,000 - $50,000 = $70,000. Thus, Josh made a profit of $70,000. \boxed{70000}

Janet's ducks lay 16 eggs per day. She eats 3 eggs for breakfast and uses 4 eggs to bake muffins for her friends. The total eggs used per day is 3 + 4 = 7 eggs. The remaining eggs are 16 - 7 = 9 eggs. She sells these 9 eggs at the farmers' market for $2 per egg. Therefore, her daily revenue from egg sales is 9 × $2 = $18. \boxed{18}

The capital of Australia is **Canberra**. Here's why: 1. **Official Capital:** Canberra was officially designated as the capital in 1913. 2. **Resolution of Rivalry:** The choice resolved a long-standing rivalry between Australia's two largest cities at the time, Sydney and Melbourne, which both wanted to be the capital. 3. **Purpose-Built City:** Canberra was specifically designed and built to be the nation's capital. It's located within the Australian Capital Territory (ACT), a separate federal territory surrounded by New South Wales. While Sydney and Melbourne are Australia's largest and most famous cities, Canberra is the seat of the federal government, hosting Parliament House, the High Court, and many government departments.

walk

Sam bought 12 boxes (a dozen) at $10 per box, so the total cost was: 12 boxes × $10/box = $120. Each box contained 30 highlighter pens, so the total number of pens was: 12 boxes × 30 pens/box = 360 pens. He repackaged the pens into packs of 6 pens each, so the number of packs was: 360 pens ÷ 6 pens/pack = 60 packs. He sold each pack for $5, so the total revenue was: 60 packs × $5/pack = $300. Profit is calculated as revenue minus cost: $300 - $120 = $180. No additional costs for repackaging are mentioned, so the profit is based solely on the initial cost and the revenue from selling the packs. \boxed{180}

As of the latest available data, PewDiePie has approximately **111 million subscribers**. To express this to the lowest million (rounded down to the nearest whole million), the number is **111**. Thus, the answer is: **111**

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