ES-237 TEST IS TOMORROW!!

1
ES-237TEST IS TOMORROW!!

• Review on geologic time

2

• List the 4 eras in order (start with the youngest
  on top)
• Place the events in each era.
• Birds
• Plants
• Oxygen
• Dinosaurs
• Horses/elephants
• Cambrian Explosion

3
Try these conversions- You must show your work!

• 345 mm _____ m
• 2. 7,500 cm ____ m
• 3. 76 km ____ m

4
Percents

• Sponges first appeared 600,000 years ago. What
  percent of the Earths history have they been
  around?
• 33 out of 50 students are wearing jeans. What
  percent is this?
• You get 23 points out of 27 points on a test.
  What is your percent correct?
• Write 1/16 as a decimal and a percent.

5
½ life

• 1. If you start with 300 g of a radioactive
  element, how many grams will be left after 3
  half-lives?
•  
• 2. What percent of the original element is left
  after 3 half-lives?
•  
• 3. If you have 1000 grams of a radioactive atom
  that has a half-life of 4 minutes how much of the
  original element will remain after16 minutes?

6

• 1. Which rock is
• the oldest?
• 2. Youngest?
• 3. Is the basalt dike older or younger than the
  sandstone layer?
• 4. Conglomerate layer?

7

• A scientist who studies fossils is a ___.
• PALEONTOLOGIST
• Nests, tracks, droppings and bite marks are
  examples of ____.
• TRACE FOSSILS
• All fossils form in ____ rock
• SEDIMENTARY
• What type of dating is used to date fairly young
  fossils of once living things?
• CARBON-14
• Atoms are radioactive because their nuclei are
  ____.
• UNSTABLE

8
When is the test????

• Tomorrow,
• Thursday, January 24!