Imagine that you are able to take a picture of a rolling ball which is slowing down. what pattern would you expect to see. Make a sketch to show your idea

The population of unionid mussels decreased after zebra mussels were introduced. zebra mussels competed with the unionid mussels for food. the zebra mussels were able to displace the unionid mussels, allowing the zebra mussel population to increase  over the years. the unionid mussel population decreased because  of lack of food.

The correct answer is:   [a]:   "polar easterlies move cool air to the mid-latitudes."