Choose the best answer. Sarah is currently spending $100 per month on electricity. She pays$0.20 per kWh. Her space heater is responsible for 10 percent of her electricity consumption. How many kilowatt-hours does her space heater use in a month? Assume a month is 30 days. (a) 0.07 kWh (b) 2 kWh (c) 20 kWh (d) 50 kWh

Consider a heat exchanger in which both fluids have the same specific heats but different mass flow rates. Which fluid will experience a larger temperature change: the one with the lower or higher mass flow rate?

Sarah belongs to an upscale gym and health spa and pays $\$90$ a month for membership. Sarah works out three times a week regularly. One day, one of the club's personal trainers came by to talk and offered to plan a routine for Sarah. The trainer had noticed that Sarah came in regularly, and commented that most members don't have the self-control to do that. In fact, she explained that there was a study of $8,000$ members in Boston-ar ea gyms showing that members went to the gym only about five times per month. The study also found that people who choose a pay-per-visit membership spend less money than people who choose a monthly or annual membership fee.

If Sarah went to the gym every day, how much would she pay per day on the monthly payment plan? Assume $30$ days in a month. If she went every day and paid $\$5$ per day, how much would she be spending per month? What percent more is this compared to the $\$90$ monthly rate rounded to the nearest percent?

Susan is currently working in Kansas City, MO earning $30,000 per year. She is offered a position in Indianapolis, IN earning$32,000 per year. If Kansas City’s Cost of Living Index is 100 and Indianapolis’ Cost of Living Index is 125, which is true?

A. Susan will have more spending power if she moves to Indianapolis.
B. Susan will have the same spending power in Indianapolis as she has in Kansas City.
C. Susan will have more spending power if she stays in Kansas City.
D. There is not enough information to decide.

Factor out the common factor. 6y-30

Use your definitions to help you answer the questions below.

a. Identify the cells that are part of the immune system.

b. Outline the steps involved in the immune response.

About 42,000 high school students took the AP Statistics exam in 2001. The free-response section of the exam consisted of five open-ended problems and an investigative task. Each free-response question is scored on a 0 to 4 scale (with 4 being the best). A random sample of 25 student papers yielded the following scores on one of the free-response questions:

Is a sample of 25 papers large enough to provide a good estimate of the mean score of all 42,000 students on this exam problem? Justify your answer.

Choose the best answer. A wooden log that weighs 1.00 kg is placed in a fireplace. Once lit, it is allowed to burn until there are only traces of ash, weighing 0.04 kg, left. Which best describes the flow of energy? (a) The potential energy of the wooden log was converted into the kinetic energy of heat and light. (b) The kinetic energy of the wooden log was converted into 0.04 kg of ash. (c) The potential energy of the wooden log was converted into 1.00 J of heat. (d) The burning of the 1.00 kg wooden log produced 0.96 kg of gases and 0.04 kg of ash.

Choose the best answer. The following table shows the efficiencies of systems providing lighting to three different houses.

$$\begin{array}{|l|c|c|c|} \hline \text{ } & \text{House A (percent efficiency)} & \text{House B (percent efficiency)} & \text{House C (percent efficiency)}\\ \hline \text{Power plant} & \text{55} & \text{33} & \text{33}\\ \hline \text{Electrical transmission lines} & \text{90} & \text{90} & \text{90}\\ \hline \text{Lighting} & \text{5} & \text{20} & \text{25}\\ \hline \end{array}$$

Overall, which represents the most efficient system? (a) House A (b) House B (c) House C (d) Houses A and B

What is the diversity of the species in an area dependent on? A. plant life 8. rainfall C. sunlight D. temperature

Choose the best answer. Which is NOT a type of organic biological molecule? (a) lipids (b) carbohydrates (c) salts (d) nucleic acids

Choose the best answer. Which statement about atoms and molecules is correct? (a) The mass number of an element is always less than its atomic number. (b) Isotopes are the result of varying numbers of neutrons in atoms of the same element. (c) Ionic bonds involve electrons while covalent bonds involve protons. (d) Protons and electrons have roughly the same mass.

Which of the following is NOT a type of organic biological molecule? (a) Lipids, (b) Carbohydrates, (c) Salts, (d) Nucleic acids, (e) Proteins.

Which statement about atoms and molecules is correct? (a) The mass number of an element is always less than its atomic number. (b) Isotopes are the result of varying numbers of neutrons in atoms of the same element. (c) Ionic bonds involve electrons while covalent bonds involve protons. (d) Inorganic compounds never contain the element carbon. (e) Protons and electrons have roughly the same mass.