1. 
At the geologists convention 1/4 of the people are students, 1/4 are professors and 1/12 are industry representatives. The rest are employees of the convention center. If there are 348 people at the convention, how many are employees of the center?


2. 
In a creek bed, 1/6 of the gravel is less than 5 mm in diameter and 1/2 of it is between 5 and 10 mm in diameter. What fraction of the gravel is greater than one centimeter in diameter?


3. 
A new island has formed off the coast of Bay City, which is not unexpected since it is near a subduction zone. The island is currently about 2 km^{2}. How many years would it take for the island to increase its area by onehalf through volcanic activity if it expands at a rate of onefourth of a square kilometer each year?


4. 
Deep in the earth's mantle near the core, the temperature is around 5000C. If the temperature on the surface near your house is 24C today, the surface temperature is what fraction of the deep mantle's temperature?


5. 
Feldspar is a common mineral on earth. By some estimates, feldspar makes up threefifths of the mineral mass in the crust. Convert this fraction to a percent.


6. 
Mr. Bloop is giving a demonstration using a water trough. This is a device used to observe (among other things) the action of water on sediments. He began with a flow rate of one and onesixth gallons per minute (gpm) and every thirty seconds he halved the rate. Throughout the demonstration the students watched small marked stones move down the trough. What was the flow rate (in gpm) after he halved the rate three times? Express your answer as a fraction.

