Answer: Nervous system.
Explanation:
Nervous system is the system in the body that consists of nerves,cells that coordinates action and sensory information and transmit nerve impulses between the body and the brain. In the body, Ghrelin is an hormone or chemical produced in the stomach. This stimulate hunger by acting on neurons in the hypothalamus which make the nerve cells that cause hunger to increase in their activity and reduce hunger inhibiting cells. The hypothalamus produce two proteins that cause hunger: neuropeptide Y (NPY) and agouti-related peptide (AGRP. This create a signals and it is send to the brain. The brain interprete it as hunger and send the signal to the hypothalamus which then influence eating behavior.
Answer: The correct answer for the first question is- B) Mechanical.
Adaptation can be described as a process of change in an organism over time that facilitates its survival in the changing environmental conditions. It results due to mutation or genetic change in the individual that gives a benefit to the organism. It exhibits change in structure ( like succulent plants in desert), function, or behavior.
Mechanical is not a type of adaptation as it deals with movement of objects.
The correct answer for second question is- C) Variations.
Variation among organisms in a population results from change in the genetic material or their genetic sequences. Change at the genetic level is thus reflected in the phenotypes ( like different color of feathers in birds).
Thus, difference is in the feather color reflects variations.
Speed = distance ÷ time.
1864/42=44.38