How do gray whales migrate?

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism

Which of the following is an eon in the time scale? phanerozoic proterozoic archean all of the above

When fossil fuels are burned, carbon dioxide is released. how does this gas impact the environment?