There are four important warning signs that should prompt you to talk to a health care provider. 1  Pain. Pain from arthritis can be constant or it may come and go. 2  Swelling. Some types of arthritis cause the skin over the affected joint to become red and swollen, feeling warm to the touch. 3  Stiffness.
There's a whole lot of water on Earth! Something like 326,000,000,000,000,000,000 gallons (326 million trillion gallons) of the stuff (roughly 1,260,000,000,000,000,000,000 liters) can be found on our planet. This water is in a constant cycle -- it evaporates from the ocean, travels through the air, rains down on the land and then flows back to the ocean.
That's a lot of water! Answer 4: The thing about the oceans is that they're all connected. However, the Atlantic covers roughly 20% of the Earth's surface, and has about 320 million cubic kilometers of water (roughly 80 million cubic miles). You likely know how long a mile is, but it might be hard to imagine 80 million cubic miles.