Does an arrowhead sometimes have 4 sides?

What is next numbers in the series 20 30 45? What are the dimensions of a highcube 53 ft trailer? Is to derive a conclusion by reasoning? Why do scientists use the Kelvin and Celsius scale rather than the Fahrenheit scale? A right triangle has a hypotenuse of length 17 and a leg of length 13 what is the length of the other leg? What is MMIV IN royal numerals? Are among the five basic postulates of euclidean geometry? How many cubic yards in a trench that is 20 foot long by 1 foot wide by 1 foot deep? What is the slope of the line y equals 6x? What is the measure of each arc of a circle that is circumscribed about an equilateral triangle? Which of these would be the most reasonable measurement for the average diameter of a penny? What is feb 19th 2009 in roman numerals? What is the correct equation for volume of a hemisphere? What are the measurements in between Milli and kilo? How would you draw a rectangular prism with a length of 8 inches a width of 4 inches and a heigh of 11 inches? How many 12x12 pavers do you need for a 10x12 patio? Can 137 tiles have only 34 tile edges? How many times is the word prostitution listed in the Bible? What x 3 equals 36? Do you say 0.0001?