Which of the following scenarios is representative of mutualism?
a.
barnacles living on whales
b.
bees pollinating flowers
c.
birds feeding on insects stirred up by grazing animals
d.
mosses living on tree trunks

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2

Moving down the ramp from 6 meters to

As a result of climate change earths temperature is rising and sea ice is melting what is a likely effect? answer : populations of walruses and polar bears will decline