A is the correct answer
population density = # of individuals/amount of area.
Answer:
One, what is consuming what
Two, Transfer of energy
A substance floats if it is less dense, or has less mass per unit volume, than other components in a mixture. For example, if you toss a handful of rocks into a bucket of water, the rocks, which are dense compared to the water, will sink. The water, which is less dense than the rocks, will float. Basically, the rocks push the water out of the way or displace it. For an object to be able to float, it has to displace a weight of fluid equal to its own weight.
Water reaches its maximum density at 4 C (40 F). As it cools further and freezes into ice, it actually becomes less dense. On the other hand, most substances are most dense in their solid (frozen) state than in their liquid state. Water is different because of hydrogen bonding.
The correct answer is C) 70/x.
To calculate doubling time, rule of 70 formula is used. For this the annual growth rate of the population is required. In this question growth rate is given x. Thus, doubling time = 70/ growth rate.
Therefore, doubling time = 70/x.
The best answer is D, birds.
For more information and details on the way a bird's respiratory system works:
https://asknature.org/strategy/air-flow-patterns-facilitate-efficient-gas-exchange/
