What is the extended and shortened structural formula for 2-methylpentane

The structural formula for 2-methylpentane is in Figure 1. It shows all the C-C and C-H bonds explicitly.

The bond-line formula for 2-methylpentane is in Figure 2. We assume that a carbon atom is at the ends and junctions of the lines. We do not show the H atom, but we mentally assume that there are enough to give each carbon a valence of four.

A condensed structural formula is designed to be typed all on one line. We could write the condensed structural formula for 2-methylpentane as either (CH₃)₂CH-CH₂-CH₂-CH₃ or CH₃CH(CH₃)CH₂CH₂CH₃.

The horizontal C-C bonds are optional — you can include or omit them as desired.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.