Answer is D. Timothy will lack testosterone and will probably be unable to achieve an erection
Covalent bonds is important in four macromolecules such as proteins (polymers of amino
acids), nucleic acids (polymers of nucleotides), carbohydrates (polymers of
sugars) and lipids (with a variety of modular constituents) because they served
as a basic structure of macromolecules.
In addition, the resulting covalent bond is a result
of sharing a pair of electrons, one from each atom or molecular units.
Answer: D is right
Explanation: It seems both waves have same wavelength.
Because speed = wavelength · frequency (v = λf) and
f = v/λ, so frequency is same. Because period T = 1/ frequency, also periods are same. Wave Y has higher amplidude and its energy is greater.