How many centimeteres is a standard ruler?

What is used to mesure huminity? Why is shapes important? How do you write 1.35 as a fraction in simplest form and as a mixed number? What is the diffrence between dependent variable and independent variable? How do you spell 153? What is the percentage of 200000 in 12370000000? What 3 digits x 3 digits equal 191862? What are the difference between a decimal and a whole number? Does O have rotational symmetry? What is the simplest form for 18 21? What is the probability that a gamete from an Rr parent carries an r allele? How many syllables in the word stormy? How many hours is there in 1000 days? What is the line of symmetry for the parabola whose equation is y equals 3x2 plus 24x - 1? What is 150 hrs divided by 2? What is 13x19? 1meter is equal to how many cm? How many syllables are in the word considered? Can the golden ratio be present within your own brain and body at the atomic or subatomic level what do you think it mean. Is this number evidence of a design a massive freak coincidence or something? What number is an integer and a natural number?