Answer:
Density is nearly 3 cabs per hectare
Explanation:
Given -
There are three three intertidal regions.
Area of each intertidal region is 
hectares.
Number of crab in the intertidal regions are as follows -
Intertidal region I - 7
Intertidal region I - 2
Intertidal region I - 6
Sum of crabs in all three regions is equal to
Total area of all three intertidal regions is equal to
hectares
Now density per hectare is equal to total population of crab divided by total area of all the three intertidal regions
Density 
Density is nearly 3 cabs per hectare
Answer:
No, bottled water cannot go bad.
Explanation:
It is impossible for any sort of water to "expire". But, when in the bottle for to long, the plastic does become dangerous. The bottle begins to leak chemicals into the water. This doesn't make the water toxic, but it can alter the taste of your water.
Answer:
The membrane is actually semi-permeable.
Explanation:
The membrane being semi-permeable means that, not all the things come in and out of the cell, only if it's really needed. The cell works in a gradient way, and that means that, to balance things, the cell will put in it a substance in a very high concentration outside of it, just to balance things. And this would happen to potassium, the cell would put it inside to balance this gradient, and once all sides have the same amount of potassium, it will stop, and the gradient is finally equal.
Phenotype; The expression of a particular trait, for example, skin color, height, behavior, etc., according to the individual's genetic makeup and environment.
The carrying capacity would *decrease*, as there are less plants for organisms to eat.
