Problem: Article: If you notice that some of the foliage is turning yellow, but not brown, leave it alone. The yellow stalks won’t affect the overall health of your plant, and cutting them down early actually decreases the amount of energy the plant can produce. Once the first frost has occurred, your lily plant no longer needs the energy produced by the foliage stalks. Use your shears to cut the yellow foliage stalks down to the ground. If quite a few of the leaves on one stem are brown, you should remove the entire stem. Follow the stem to the base of the lily plant, then use pruning shears to cut off the entire stem. Be sure you don’t leave a stub at the base of the plant. If you notice that just the tips of the leaves on your lily plant are browning, you don’t need to remove the whole stem. Instead, make an angled clip just below the browning tip. The plant should grow a new healthy green tip.
Summary: Leave yellowing or browning stalks until the fall. Prune back yellow stalks after the first frost. Remove entire stems of mostly brown leaves. Clip the tips of browning leaves.

INPUT ARTICLE: Article: The standard equation for absorbance is A = ɛ x l x c, where A is the amount of light absorbed by the sample for a given wavelength, ɛ is the molar absorptivity, l is the distance that the light travels through the solution, and c is the concentration of the absorbing species per unit volume.  Absorbance can also be calculated using the ratio between the intensity of a reference sample and the unknown sample. It is given by the equation A = log10(Io/I).  Intensity is obtained using a spectrophotometer. The absorbance of a solution will change based on the wavelength that is passed through the solution. Some wavelengths will be absorbed more than others depending upon the makeup of the solution. Remember to state which wavelength is being used for your calculation. Using algebra we can divide absorbance by the length and the concentration to get molar absorptivity on one side of the equation: ɛ = A/lc. We can now use this basic equation to calculate molar absorptivity for a given wavelength. Absorbance between readings can vary due to the concentration of the solution and the shape of the container used to measure intensity. Molar absorptivity compensates for these variations. A spectrophotometer is a piece of equipment that passes a specific wavelength of light through a substance and detects the amount of light that comes out. Some of the light will be absorbed by the solution and the remaining light that passes through can be used to calculate the absorbance of that solution.  Prepare a solution of known concentration, c, for analysis. Units for concentration are molar or moles/liter.  To find l, measure the length of the cuvette, the piece that holds the liquid samples in the spectrophotometer. Units for path length are measured in centimeters. Using a spectrophotometer, obtain a measurement for absorbance, A, at a given wavelength. The unit for wavelength is meters, but most wavelengths are so small, they are actually measured in nanometers (nm). Absorbance has no units. Using the values you obtained for A, c, and l, plug them into the equation ɛ = A/lc. Multiply l by c and then divide A by the product to solve for molar absorptivity. For example: Using a cuvette with a length of 1 cm, you measured the absorbance of a solution with a concentration of 0.05 mol/L. The absorbance at a wavelength of 280 nm was 1.5. What is the molar absorptivity of this solution?  ɛ280 = A/lc = 1.5/(1 x 0.05) = 30 L mol-1 cm-1

SUMMARY: Understand the Beer-Lambert law for absorbance, A = ɛ x l x c. Rearrange the Beer-Lambert equation to solve for molar absorptivity. Obtain values for the variables in the equation using spectrophotometry. Plug in the values for the variables and solve the equation for molar absorptivity.

In one sentence, describe what the following article is about: Reading is the foundation for gaining any type of general knowledge. There are no specific requirements on what books to read or on what subjects since the acquisition of general knowledge incorporates a wide-range of topics. The most important quality of reading is to make it a daily and routine part of your day.  Get a membership at the local public library. Memberships are often free or inexpensive, giving you access to thousands of books with friendly return dates. Go to a yard or garage sale. You can stock up on cheap books on a range of topics that you might not otherwise spend money on. Purchase an e-reader to download reasonably priced books and articles from a variety of websites. This will give you instant gratification and more knowledge. Newspapers are great sources of local, regional, national, and worldly news. Some are better than others, but newspapers offer reasonably updated information on politics, sports, fashion, food, and a diversity of other interests.  Try to make reading the newspaper one of your morning habits. A newspaper can be delivered to your doorstep before you even wake up, giving you few excuses to use it as a valuable resource in your pursuit of knowledge. Most newspaper publishers offer online subscriptions at a lower cost. If you prefer to receive your information digitally, then you should consider one of the many newspapers available to you at a click of a button. If you work for a company, they usually subscribe to the New York Times, Wall Street Journal, or the Washington Post. Take advantage of this freebie and gain knowledge while at work. Go to a bookstore and you will find several rows of unending magazines lined up for your perusal. Magazines are everywhere and cover every topic. Although you might not want to subscribe to a magazine service like Publisher’s Clearing House, there are numerous other options available.  Pick up a magazine at the local grocery store while your family shops for food. Nobody ever got escorted out of a supermarket for standing in front of the magazine rack for thirty minutes. When you are at a doctor, dentist, or automobile appointment, take advantage of all the popular magazines available to you in their waiting rooms. Usually they have Time, Newsweek, and some entertainment magazines for you to read while you wait. Journals typically provide academic research that are longer than magazine articles and use extensive citations. A journal contains very specific information about one particular discipline. Compared to books, newspapers, and magazines, journals are more difficult to access and are more expensive, but provide more detailed and proven information.  If you prefer the academic nature of a journal, then join a society that you are interested in like history, biology, or sociology. These societies fund journals and send them to members who are interested in the same fields of knowledge. Go to a university library where you can access hundreds of different journal titles on nearly any academic topic.
Summary: Read a book. Subscribe to a newspaper. Browse through a magazine. Sit down and peruse a journal.

In one sentence, describe what the following article is about: Your worms can tolerate temperatures as low as 40 degrees Fahrenheit (4 C) and as high as 90 degrees Fahrenheit (32 C).  The lid will also keep birds and other natural predators out of the worm bed. Red wigglers dislike light, and the light will train them to stay in the dark bin. Two pounds (0.9 kg) of worms will eat about 1 pound (0.45 kg) of scraps daily. Doing this will control the size of the worm population. You can use your worms as fishing bait, if you wish.
Summary:
Place the worm bed in a dark area that is between 60 to 80 degrees Fahrenheit (15 C to 27 C). Add about 2 pounds (0.9 kg) of red wiggler worms to the top of the worm bed. Place the fabric-lined lid on top of the box to block out the light and to keep the worms in their bed. Turn a light on near your worm bed. Feed the worms with scraps from your kitchen. Pick larger worms out of the worm bed every couple of months.