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:
- T. Natural Reseeding.
- D. Species Diversity
- A. Ecosystem Diversity.
Explanation:
Natural reseeding uses natural elements and actors to plant the seeds of trees. These elements and actors include water, wind, birds, rodents and other actors capable of scattering seed.
Species diversity is what defines the differentiation between the different species in an ecosystem and Ecosystem diversity relates to how biological communities/ ecosystems can be different from each other based on the organisms and food chains available in each.
Answer:
Mitosis
Explanation:
Mitosis is not a source of genetic mutation because it take place mostly in the somatic cells. This is because it does not lead to the production of gametes . In mitosis, the parent cells divide into two daughter cells and each daughter cells are genetically identical to the parent cell because they carry the same number of chromosomes as the parent cell. There is no genetic variation in this.
Answer:
A The book on the table
Explanation: It is at rest which mean its in equilibrium