Ignore the dots, just put them in to line things up.

Question

1. What is the asymmetric carbon
5...4...3..2..1
CH3-CH2-CH-CH-CH3
........|..|
CH3.CH3

2. which of the following compounds have an asymmetric carbon?

A. CH3-CH-CH-CH3
........|..|
........OH.CH3

B. CH3-CH-CH3
........|
........CH3

C. CH3-CH-F
........|
........OH

Answer 1

The asymmetric carbon for the first one is #3 by your numbering system.

The periods don't help that much but I can guess where the substituents go from the number of H atoms attached for the second question.
A has an asymmetric carbon on #2 (first C on left is #1), B has none, and C has one on #2 carbon (first C on left is #1).
Check my thinking.