Please focus on the following topics when you study for the quiz:

1. Metric to Metric Conversions
   Keep the "Metric Number Line" in mind or immediately draw it on your quiz for quick reference.
   Km-----Hm-----Dm-----m-----dm-----cm-----mm

   Count the number of steps (right or left) to get from the given unit to the desired unit. Then move the decimal place of the given unit an equal number of steps to the right or left to achieve the desired unit answer.

2. English to Metric Conversions
   You will need to set up a cross product and use the proper conversion factor to achieve the answer.
   1. Set the given quantity of units equal to X (ex. 10 lb = X)
   2. Draw a line under each side of the equation
   3. Denominator units match the numerator units (ex. 10 lb./lb. = X/Kg)
   4. Fill in the conversion factor in the denominator of both sides (ex. 10 lb./2.2 lb. = X / 1 Kg)
   5. Solve for X.

3. Temperature Conversions
   Memorize the three different temperature formulas. Remember that Kelvin has no "degree" symbol.

4. Calculating Mean & Median
   • Mean - sum of all data points divided by the number of data points.
   • Median - list all data points from highest value to lowest value. If an ODD number of points, the median is the middle value. If an EVEN number of points, the median is the mean of the two middle points.

5. Calculating Environmental Temperature Lapse Rate (ELR)
   To calculate the ELR, one needs two temperatures at two different altitudes (heights). One also assumes that the rate of temp change between these two points is constant (straight line slope). To calculate, use the formula (T2-T1)/(H2-H1) where T is temperature and H is height. Answers must always be reduced to degrees F per 1,000 feet.

   Example:
   The air at 2,000 feet is 40 degrees F while the air at 6,000 feet is 10 degrees F. Calculate the ELR.

   1. Jot down the two points being considered: T1 = 40 F, H1 = 2,000ft., T2 = 10 F, H2 = 6,000 ft.
   2. Use the formula: (10F - 40F)/(6,000ft. - 2,000ft.)
   3. Result = -30F/4,000ft. Divide top and bottom by 4 to reduce the ratio to F/1,000 ft.
   4. Answer: -7.5F / 1,000ft.

6. Using the ELR to Estimate an "In-Between" Temperature
   The previous ELR means that the air temperature is cooling 7.5 F for each 1,000 feet of elevation. Therefore, one can use this ELR value to estimate any temperature between 2,000 and 6,000 feet. For example, if one wanted to estimate the temperature at 4,000 feet, the ELR shows that there should be a decrease of 15 F (2 x 7.5) moving from 2,000 feet to 4,000 feet. Since the air at 2,000 feet is 40F, the air at 4,000 feet is 25F (40F - 15F).

Helpful Links:

Practice Problems (PDF format)
U.S. Metric Association
About Temperature
Calculating Mean & Median