Ken is a microbiologist. He got two samples of yeasts, yeast A and yeast B, from two different businesses. Yeast A is used in a bakery, and yeast B is used in a brewery. He has to decide the characteristics of each yeast sample for further study. Interestingly, despite all his curiosity, Ken doesn't like any yeast to be around him. If Ken wants a dough sample to expand, which yeast should he use, yeast A or yeast B? Hint: Baker's yeast is the common name for the strains of yeast commonly used in baking bread and bakery products, serving as a leavening agent which causes the bread to rise (expand and become lighter and softer) by converting the fermentable sugars present in the dough into carbon dioxide and ethanol. Baker's yeast is of the species Saccharomyces cerevisiae,[1] and is the same species (but a different strain) as the kind commonly used in alcoholic fermentation, which is called brewer's yeast.[2] Baker's yeast is also a single-cell microorganism found on and around the human body.
Ans: yeast A

In his chemistry lab David is experimenting with how NaOH and HCl gas reacts with each other. He conducted two experiments, experiment A and experiment B. In experiment A he used solid pellets of NaOH, but in experiment B he used ground NaOH. He was surprised to see the difference it made in his experiment. Would experiment B's hydroxide have smaller or larger surface area than experiment A's hydroxide? Hint: For example, if a solid pellet of NaOH is placed into a chamber of HCl gas, a relatively slow acid-base reaction will occur between gaseous HCl molecules and hydroxide ions on the surface of the pellet. If we were to grind the pellet into smaller pieces, it would greatly increase the total surface area, and therefore the overall reaction rate. Once ground up, many hydroxide ions that were on the interior of the pellet, where they were not exposed to any HCl molecules, will now be on the surface, where the necessary collisions can occur.
Ans: larger

In the Kenya-Tanzania border Kenyan grassland gradually merges into Tanzanian forest. Though they had similar soil to start with millions of years ago, today they are two different habitats. At present, Kenya has one of the largest contiguous grassland in Africa. On the other hand, Tanzania boasts one of the largest forest cover in Africa. Which place would have thinner "A horizon", Kenya or Tanzania? Hint: In grassland, much of the organic matter added to the soil is from the deep, fibrous, grass root systems. By contrast, tree leaves falling on the forest floor are the principal source of soil organic matter in the forest. Another difference is the frequent occurrence in the grasslands of fires that destroy large amounts of aboveground material but stimulate even greater contributions from roots. Also, the much greater acidity under any forests inhibits the action of certain soil organisms that otherwise would mix much of the surface litter into the mineral soil. As a result, the soils under grasslands generally develop a thicker A horizon with a deeper distribution of organic matter than in comparable soils under forests, which characteristically store most of their organic matter in the forest floor (O horizon) and thin A horizon.
Ans: Tanzania

Jenna is studying waves and their related characteristics. Today, is she analyzing two different waves, wave D and wave M. Wave D has a very long wavelength, and wave M has a short wavelength. In order to verify her findings though, she is going to stand still and have both waves pass over her for the same amount of time and record the number of waves of each type that passed her. Will more wave D or wave M waves pass Jenna? Hint: Figure B above shows an important relationship between the wavelength and frequency of a wave. The top wave clearly has a shorter wavelength than the second wave. However, if you picture yourself at a stationary point watching these waves pass by, more waves of the first kind would pass by in a given amount of time. Thus the frequency of the first waves is greater than that of the second waves. Wavelength and frequency are therefore inversely related. As the wavelength of a wave increases, its frequency decreases. The equation that relates the two is
Ans: wave M