**First station: Rocks and minerals**

Your first mission on the Earth Science Lab Practical is to carefully conduct all the mineral tests.

For the hardness and streak tests, it’s necessary to ensure your mineral is firmly against the glass. Make sure to position the glass such that it’s perfectly flat on the table.

Predictable breaks are cleavage. Unpredictable and random breaks are fractures.

To “have a metallic luster,” a mineral must really look like a piece of metal.

You will need to identify your mineral using a flowchart.

When identifying rocks, make careful observations, as in the following example:

*Rock type: Possible reasons*

*Igneous: Intergrown mineral crystals, glassy texture, vesicular texture*

*Sedimentary: Includes pieces of other rocks, sediments cemented together, shell fragments cemented together, fossil imprints, layers*

*Metamorphic: Banding, mineral alignment (foliation)*

**Second station: Locating epicenters**

For Regents exam questions that provide the distance from the epicenter, set the compass distance using the map scale, and use the station as the center to draw the circle.

Some questions on the Earth Science Lab Practical will give you the arrival times of P-waves and S-waves. Calculate the difference, and then use the ESRT chart to determine the distance to the epicenter. Then draw the circle using the map scale.

You might have to use time math. Should you need to borrow, borrow 60.

Once you have three circles, you should be able to pinpoint an exact (or almost exact) intersection point. If you can’t, double-check your work and revise accordingly.

**Third station: Eccentricity**

Put your paper on your box and insert the push-pins into the provided focal points.

Wrap the string around the push-pins, and draw the ellipse while holding your pencil perfectly upright.

*d*is equal to the distance between the two push-pins (foci).*L*is equal to the distance from one end of the ellipse to the other via the two foci (major axis).You shouldn’t end up with an eccentricity greater than 1. Try again with the numbers flipped.

The closer the eccentricity is to 0, the more it resembles a perfect circle.

The closer the eccentricity is to 1, the less it resembles a perfect circle.

The Earth Science Lab Practical gives precise instructions. You’ll lose points if you don’t round to the instructed decimal place.

Orbiting planets experience the fastest velocity and strongest gravitational pull at the perihelion (when the planet is closest to the star). Similarly, the slowest velocity and weakest gravitational pull are found at the aphelion (farthest from the star).

Page 15 of the ESRT provides the eccentricities of planets in orbit.

**General Tips**

1. Follow these tips for measuring:

Measure using the centers of points.

Round as per the instructions. Add “.0” if necessary.

In rounding, numbers 5 and higher round up.

The Earth Science Regents Exam demands precision, not rough estimates.

2. Read all the directions carefully.

3. If a question asks you to explain why, for example, a rock type is a certain way, you can’t explain why it isn’t a different way.

4. There are no units in eccentricity because it is a ratio.

5. When using a calculator for division, don’t flip the numbers. For example, 1/2 and 2/1 are very different numbers.

6. Don’t write more than what the question is asking.

The key to doing well is to answer all the questions and be confident. A private Regents tutor is always a worthwhile investment to enhance your skills and knowledge and boost your confidence, maximizing your chances of success.

## Comments