Vertebrates first appeared in the ____

A rock sample containing an isotope with a half-life of 28 million years has an initial mass of 184 grams. How much

daughter isotope is present after three half-lives? a. 23 grams b. 46 grams c. 69 grams d. 115 grams e. 161 grams

The map below uses what type of map projection?

A. conical B. sinusoidal C. cylindrical D. planar

In 1992, the Canadian government ________

A) banned the use of trawl fishing B) started harvesting manganese nodules from the ocean floor C) ordered a complete ban on cod fishing D) enacted laws to protect many species of whales E) gave subsidies to fishermen who were losing money due to low fish harvests

Which of the following kingdoms includes the blue-green algae?

A) Archaebacteria B) Eubacteria C) Fungi D) Plantae E) Protista