It is important because you need vitamins and minerals from them e.g. Scurvy no vitamin c
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
Es una descendencia. es un nuevo organismo
Answer:
Additional Information: Mutualism is the relationship where both organisms get positive results from it. An example of mutualism is the relationship between remora and shark.When one organism lives on another organism, that type of symbiotic relationship is called parasitism.
Tar and other ingredients found in smoke act as carcinogens which can cause an uncontrolled growth of cells