Earth's physical layers in sequence

In the following diagram, four different index fossils are labeled: which of the labeled fossils comes from the oldest organism? a b c d

Which of these has the least impact on the climate of a place

What must happen for new french words to be published in official dictionaries? a. they must be approved by the french academy b. they must be voted on by the people of france c. they must be used by famous french writers d. they must be used by philosophers a. they must be approved by the french academy