For each pair, give the relationship between the two compounds. Making models will be helpful. (a) (2R, 3S)-2, 3-dibromohexane and (2S, 3R)-2, 3-dibromohexane
(b) (2R, 3S)-2, 3-dibromohexane and (2R, 3R)-2, 3-dibromohexane

(a) Enantiomers

(b) Diastereomers

Explanation:

In the first pair of molecules, we have an opposite configuration. That is, in the first molecule we have an R and S configuration and in the second an S and R configuration. Therefore we have a mirror image, if this is true, we will have a mirror image and we will have "enantiomers". (See figure 1)

In the second pair of molecules, we do not have a mirror image. Since the first molecule has an R, S configuration (the mirror image would be S, R). In the second molecule, we have an R, R configuration (the mirror image would be S, S). Therefore, the relationship between these molecules is "diastereoisomers". (See figure 2)

the answer is 1260

you spend 7 hours in school for 1 school day with 5 school days in 1 school week with 36 school weeks in a school year.

7*5*36= 1260 it's all about multiplying