hooc are carboxyl groups
your r or amino groups are those unique structures which have different atoms in them. your nh2 groups are your hydrogen atoms
The relative mass of each element can be found from the periodic table (the larger number). For instance, P2O5, P = 31.0 O = 16.0, thus the formula mass (Mr) is 2(31) + 5(16) = 142 amu (atomic mass unit). I used a not really specific periodic table. Maybe your teacher is referring to open Schoology (a website where teacher can post files or announcements to students in his or her class). Sorry if i got something mistaken.
Hey mate!
Taxonomy is the <span>study of classification of organisms. Therefore, your answer is A.
Hope this helps!</span>
