In one sentence, describe what the following article is about: A multi-cell battery is when you connect multiple batteries together. In this case, you will link multiple lemon batteries together. To make a multi-cell lemon battery you will need four copper pennies, four galvanized nails, four lemons, a knife, 15 inches of copper wire, wire cutters, a ruler, and a voltmeter. Any lemon will do, but a lemon with a thinner rind will make a better battery. Adult supervision is strongly recommended, particularly when using the knife. Clean the penny with a light detergent to maintain a clean working surface. If you have one, a lobster claw will do. Galvanized nails have a zinc coating that is important to this experiment and can be found at a local hardware or home improvement store. Aluminum foil can be substituted for the nail if you don't have one. You can link as many lemons together as you'd like to increase the voltage.
Summary: Gather your tools.

In one sentence, describe what the following article is about: R-value is a measure of how well an insulation does its job of reducing hot or cold airflow. A higher R-value, per inch of thickness, indicates better insulation. The R-value you will need depends on the climate where your home is located and on how well insulated you'd like your home to be. For example, if you live in a warm climate, you would want a minimum value of R-30. Cold climates would require a minimum value closer to R-60. R-value will help you choose the level of insulation that you'll need. There are many basement insulation types. Three of the most popular types of insulation are batt-and-roll (blanket), loose-fill, and sprayed-foam. For blanket or batt-and-roll insulation, simply nail or staple the insulation into your wood frame. Blanket insulation is usually available in standard wall-frame sizes. For loose-fill insulation, install drywall over the studs before adding the loose-fill insulation. Sprayed-foam insulation is the most energy-efficient option for insulating a basement. It may be necessary to rent equipment to insulate your basement with wet-sprayed cellulose. This equipment is available at most major hardware stores. Sprayed foam can be open-cell or closed-cell. Open cell simply means there is air between the many bubbles made by the sprayed foam. Closed-cell, though slightly more expensive, is filled with non-air chemicals that are more efficient at insulation. Additional treatments can help protect against moisture and can be more fire retardant. Faced insulation uses vapor barriers that control moisture movement between walls. Unfaced insulation does not have vapor barriers, but you might not need a vapor barrier if, for example, you're applying over existing installation or if moisture control is unnecessary. Fire-rated coverings are often necessary, since many types of insulation release toxic gases when ignited. Consult your local building code to see if this is necessary.
Summary: Choose an R-value. Evaluate your insulation options. Consider additional treatments for your insulation.

In one sentence, describe what the following article is about: If you notice any spots around the back of your braid that look loose or in danger of falling out of the braid, then you might want to reinforce them with a couple of bobby pins. To use a bobby pin, open up the bobby pin and then slide it over the loose piece and connect it to some of the hair on your scalp. You will probably need a couple of bobby pins for each loose strand. It is okay if the braid looks messy with a few loose strands near the front, but you don't want it coming undone completely. If your braid looks a little thin, then you can gently tug on the sides of your braid to widen it. Start near the top the braid and grab a couple of pieces on opposite side of the braid and pull them apart slightly. Do not pull too hard or you may undo part of the braid. Just pull enough to make the braid look a little wider and looser. If you want your Katniss braid to last all day, then finish it with an all over mist of strong hairspray. Spray the braid, back of your head, sides, and loose pieces. Make sure that you close your eyes and hold the can about 12 to 18 inches from your head.
Summary:
Add bobby pins to secure any loose back pieces. Tug the sides of the braid to widen it. Spray on some hair spray.