The first jawed fish were the:a. placoderms. b. acanthodians. ...

[tth]

The first jawed fish were the:a.
   placoderms.
  b. acanthodians.
  c. ostracoderms.
  d. chrondrichthyes.
  e. agnatha.

Question 2

The mass extinction at the end of the Ordovician set the stage for:a.
   more species to go extinct.
  b. groups of organisms to diversify.
  c. groups of organisms to withdraw from previous habitats.
  d. groups of organisms to repopulate abandoned niches.
  e. groups of organisms to diversify AND to repopulate abandoned niches.

[bimper21]

Answer to Question 1

B

Answer to Question 2

E

[tth]

Wow, this really help

[mcarey591]

Excellent