Rebecca tells Tom that he is singing “off pitch.” Rebecca is referring to Frequency of sound.
Frequency is measured as the number of wave cycles that occur in one second. It is defined as the speed of the vibration and this further determines the pitch of the sound. This is usually useful for musical sounds where there is a strong waveform.
Answer:
when it's born a star is born when it's born
2. Antigen
Toxins
3. Some bacterial infections
Viral
4. Innate immune system
5. Adaptive
6. Leukocytes
7. Humoral response
Cell mediated response
8. B cells
T cells
9. Helper T cell
Cytotoxic T cell
10. Antibody production.
Natural selection<span> is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.</span>