If you mean what group of elements react the most, the answer is the alkali metals and the halogens because they both only either need to gain or lose one electron. If you mean the most reactive element, it would be fluorine because it has the most electronegativity.
Answer:
Tryptophan is an essential amino acid.
The correct answer among the choices given is option A. Eustachian, Pharynx, Bronchi are structures that ensembles a tube. The Eustachian tube is a narrow passage from the pharynx to the middle ear. Pharynx is a passageway leading from the oral and nasal cavities to the larynx and the esophagus. Lastly, bronchi is an airway in the respiratory tract.
Answer is
C. 2.07 M
For explanation
M1V1 = M2V2
M2 = (M1V1)/V2
M2 = (1.5M x 345ml) / 250 ml
:. M2 = 2.07 M