How Much Do Diamond Engagement Rings Cost. There are two major factors which contribute to the cost of a diamond: a ratings system called the âFour Csâ and whether or not the diamond is ASG/GIA certified. The Four Cs refers to the diamondâs color, cut, clarity, and carat size.
Best Answer: A wind vane is used to tell wind direction. The National Weather Service and those that have a lot of money use a Aerovane. Aerovanes are commonly used at many weather stations and airports to measure both wind direction and speed.
These types of instruments are used by the wind energy industry, both for wind resource assessment and turbine control. Wind speed is measured with an anemometer. In situations where modern instruments are not available, an index finger can be used to test the direction of wind. This is accomplished by wetting the finger and pointing it upwards. The side of the finger that feels cool is (approximately) the direction from which the wind is blowing.