How many hectare are in a 10 Km circumference?

Where and when did the expression laid back originate? How many times is the word need mention in the Bible? Is a postivie plus a negative a negative? 300 usd is equal to how many rupees? What is the slope of a line perpendicular to a line with a slope of -11 divided by 13? How much is six and six tenths in inches? How many pint to a gallon? How many minutes is in 2 how many minutes are in 2 hours and 30 minutes? What does dots beside iii brainteaser mean? Are socks symmetrical? What is 14 sided shape called? What is the shabd roop of vanam? How many minutes are there in three quarters of an hour? How many feet are in 2.72 meters? Find 3 consecutive numbers where the product of the smaller two numbers is 40 less than the square of the largest number? Is 10 over 20 equal? What is the 37th prime number? What do you call it when two lines meet? An airplane is flying at 400 miles per hour due west The wind is blowing from due north at 30 miles per hour what is the speed and direction of the plane? 1.8 micrometers to liters?