What is the structure of 3-isopropyl-4-methylhex-2-ene? Does it have stereoisomers?

Are the molecules shown below isomers or identical?

Provide the structural formula for the isomers of n-hexyne that can be created by shifting the triple bond's position

Structural isomerism occurs when the atoms that form a molecule have different connectivities with one another. Which of the following properties are expected to be different for 1-bromobutane and 2-bromobutane?
(a) Chemical formula, (b) Boiling point, (c) Viscosity, (d) Vapor pressure.
You can find out the physical properties of these two substances in the CRC Handbook of Chemistry and Physics.

Identify the pair of isomers: