Answer:
By looking at human embryo we can determine that it has a postanal tail.
Explanation:
Human embryo is a a process of life cycle that takes place after the fertilization. It takes 9 months for a human embryo to be fully developed. If we take a look at a human embryo, we will notice that it has a postanal tail.
Postanal tail is simply an extension of body. It is only during the embryonic stage that the postanal tail can be found. After the birth this feature cannot be found.
X and Y because females are X and X.
D) neither photosynthesis nor respiration.
The kingdom described above is the kingdom Animalia. Heterotrophic mode of nutrition is a type of nutrition in which organisms depends upon other organisms such as plants for survival, for example all animals are heterotrophic and obtain all organic materials they need to survive. The other type of nutrition is the autotrophic mode of nutrition in which organisms use simple inorganic substances to synthesize organic molecules, a characteristic of plants.
The answer is 44 chickens and 28 rabbits.
We have a system of two equations.
x - the number of rabbits
y - the number of chickens
Both chicken and rabbit have only 1 head, so the first equation is: x + y = 72.
Since rabbits have 4 legs and chickens 2 legs, the second equation is: 4x + 2y = 200.
Now, let's solve the system:
x + y = 72
4x + 2y = 200
___________
y = 72 - x
⇒ 4x + 2 · (72 - x) = 200
4x + 2 · 72 - 2 · x = 200
4x + 144 - 2x = 200
2x + 144 = 200
2x = 200 - 144
2x = 56
⇒ x = 56 ÷ 2 = 28
So, there are 28 rabbits.
Since
y = 72 - x = 72 - 28 = 44,
there are 44 chickens.