In one sentence, describe what the following article is about: The radius is the distance from the center of the circle to its edge. π is equal to approximately 3.14 but you should use your calculator to get the most accurate results. This goes back to manipulating the formula for finding the area of a circle, A = πr2, to get the diameter. You can transform this into r = √(A/π) cm.
Summary: If you know the radius of the circle, double it to get the diameter. If you know the circumference of the circle, divide it by π to get the diameter. If you know the area of the circle, divide the result by π and find its square root to get the radius; then multiply by 2 to get the diameter.

In one sentence, describe what the following article is about: It is easier to melt almond bark when it has been cut into smaller pieces. If your almond bark came in small disks, as it sometimes does, you do not need to chop it up. A double boiler is made up of two components--a large pan filled with water and another, smaller pan that sits on top. Double boilers help to ensure that your chocolate does not burn while you are melting it because you are heating it indirectly through the use of both pans. Place the top pan containing the chocolate on top of the larger pan with the water. Turn the heat to medium to high heat. The bark will begin to melt almost instantly. Stir it to keep the bark from burning. When all of the chunks are melted, turn the heat off and remove the top pan from the lower one.
Summary: Chop your almond bark into small pieces. Place the almond bark in the top part of the double boiler. Fill the bottom pan with water. Stir the almond bark constantly.

In one sentence, describe what the following article is about: You can also make a fireball using a cotton shirt as a base, which will make a bigger flame. First, cut the cotton T-shirt into a 2 x 4.7 inch(5 x 12 cm) strip. Make sure that you are using a T-shirt that is 100% cotton. If you use a shirt that is only partly cotton, it will melt instead of burn. After you cut your strip, roll it to create a ball. Try not to roll it too tightly, or else the rubbing alcohol will have a hard time soaking into the fabric. Also try to tuck in any loose ends or edges to make a more regular ball. Keep holding the cloth ball in your hand after rolling so that it doesn’t unravel. Thread a large, sharp needle with cotton string. Then insert the needle into the cloth ball, piercing it all the way through the ball from one side to the other.  Make sure that the string you are using is 100% cotton. Hold the ball while you pierce it with the needle to make sure it stays together. After you stitch through the cloth ball, tie the cotton string at both ends. Stitching through the ball helps the cloth ball to keep its shape. Don’t break off the string, as you will keep using it. After you have stitched through the middle of the ball, take the cloth thread and wind it around the ball to help hold it together and keep its spherical shape. After you have wound the thread around the ball, insert the needle back into the ball and pull the string through the other side. Then cut the string and knot it so that it stays. Pour around ½ cup (125 ml) of rubbing alcohol into a bowl large enough to hold the cloth ball. Then take the cloth ball and place it in the rubbing alcohol, allowing it to soak for a few seconds. Use a spoon or other object to turn the ball over in the alcohol so that both sides absorb some of the rubbing alcohol. Do not get any rubbing alcohol on your hands or clothes. After you have soaked the cloth ball for about three seconds, use a pair of tongs or tweezers to transfer the ball out from the bowl with the alcohol to a new, clean bowl. Make the transfer after only a few seconds so that the cloth ball doesn’t soak for too long. If the ball absorbs too much rubbing alcohol, it will become soaked and start dripping. This can be dangerous when you light it on fire.
Summary:
Cut a shirt into a strip. Roll the strip of shirt into a ball. Fasten the ball with thread. Tie the string at both ends. Wrap thread around the ball. Secure the thread. Place the cloth ball in a bowl of rubbing alcohol. Transfer the cloth ball to a clean bowl.