Give the effect of the configuration of `(S)-2-` bromo butane on performing the following operations:
a. Exchanging ligands across the horizontal bond.
b. Exchanging ligands across the vertical bond.
c. Making both switches (a) and (b)
d. Exchanging a horizontal and vertical ligand.
e. A `180^(@)` verticle or horizontal rotation outside the plane of paper.
f. A `90^(@)` rotation on the plane of paper.

Explanation

To determine the effect of the configuration of (S)-2-bromobutane on various operations, we will analyze each operation step by step.

### Step-by-Step Solution:

1. **Understanding the Structure of (S)-2-bromobutane:**
- (S)-2-bromobutane has the following configuration:
- The bromine (Br) is attached to the second carbon.
- The other groups are: a methyl group (CH3), an ethyl group (C2H5), and a hydrogen (H).
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