How many diagonals does a icosogon?

How high is 66cm? How many laps do you swim in an 25 m pool to make a mile? Why do i see the number 14 in school everywhere? Can a zero be negative? What is the function of a sifter? Is 1 and one sixth greater than 1 and five eighteenths? What is one verre equal to? How many grams in a kilogram of yarn? How many square feet in 10 ft? What number is a squared number and cubed number? What is 237000 in scientific notation? What shape has 4 right angels and 2 pairs of equal sides? What is the average of 23-65-71? How do you find the area of 2in and 7 in? What would be the decimal between 005 and 006? How many times does 35 go into 45? What is 6300m in km? How do you find the area of a figure to the nearest tenth of a unit? What is the integer of 112 Fahrenheit above 0? How do you write 1 trllion in words?