What is the ratio of 21 to 13?

What is the answer to negative 38 plus negative 56? Which is larger 1km or 1m? What will be the volume of a cylinder that's dimensions are doubled? What do parentheses with bumps mean? How is 86.04 written in word form? How many sides do a nonagon and a quadrilateral have altogether? What temperature is 220 degrees F in degrees C? If the diameter of a circle is 16 cm what is the circumference of the circle? How long is 18 days in weeks? What is the average deviation of 5 5 5 5 5? How do you write 2.243 in words? How far is 29000 steps? What is the remainder of 21 divided by 4? Is the sum of the area of the faces of a three dimensional figure? What if the difference between two numbers is sixteen three times the larger number is seven times the smaller what are the numbers? What is 9.46 trillion kilometers equal to? What is a hjg? What is 0.82 as a fraction in simplest from? What is ten to the power of 9? What type of virus is associated with acute febrile pharyngitis?