The flow of nutrients through a biotic community is ________. ...

[tingc95]

The flow of nutrients through a biotic community is ________.
 
  A) cyclic and multidirectional
  B) cyclic and unidirectional
  C) noncyclic and multidirectional
  D) noncyclic and unidirectional

Question 2

How do centripetal forces and gravitation forces interact to produce the tides?
 
  What will be an ideal response?

[elyse44]

Answer to Question 1

A

Answer to Question 2

The tide-generating forces create two simultaneous bulges: one on the side of Earth directed toward the Moon (the zenith) and the other on the side directed away from the Moon (the nadir). On the side directly facing the Moon, the bulge is created because the provided gravitational force is greater than the required centripetal force. On the side facing away from the Moon, the bulge is created because the required centripetal force is greater than the provided gravitational force. Although the forces are oriented in opposite directions on the two sides of Earth, the resultant forces are equal in magnitude, so the bulges are equal.