Answer:
With less energy at higher trophic levels, there are usually fewer organisms as well
Explanation: Organisms tend to be larger in size at higher trophic levels, but their smaller numbers result in less biomass. Biomass is the total mass of organisms at a trophic level.
Answer: 4. 
and 
Explanation:
a) The given reaction is 
As the mass on both reactant and product side must be equal:
As the atomic number on both reactant and product side must be equal:
b) 
Total mass on reactant side = total mass on product side
15 =15 + x
x = 0
Total atomic number on reactant side = total atomic number on product side
8 = 7 + y
y = 1
Answer:
The water soluble substance which absorb moisture from the air and then dissolve on the absorbed moisture to change into liquid taste are called deliquescent substances whereas the substances which absorb moisture from air but do not change their state are called hygroscopic substances.
Changes to genes can affect the phenotypic traits of an organism, making them look differently.
Answer:
Muscular contractions that moves food along the digestive tract.
