In the given reaction the number of sp 2 hybridised carbon (s) in compound ' X ' is _______.

In the first step oxidation of cyclohexanol to cyclohexanone by acidified potassium dichromate takes place.

In the second step cyclohexanone reacts with grignard reagent followed by hydrolysis to form a tertiary alcohol.

In last step dehydration of tertiary alcohol leads to the formation of  

In the above molecule the number of sp² hybridized carbons are 8.