Which best describes the relationship between the terms “frequency,” “wavelength,” and “hertz”? Wavelength is the number of frequencies, which is measured in hertz.
Frequency is the number of wavelengths, which is measured in hertz.
Wavelength is measured from frequency to hertz.
Frequency is measured from wavelength to hertz.

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.

because if the tool that you are using is not balanced it there would be false mass.