Is the carbon atom in CH2=CH-CH2-CH=CH2 coplanar? RT

Is the carbon atom in CH2=CH-CH2-CH=CH2 coplanar? RT

Shouldn't be coplanar.
The middle methylene is sp3 hybrid.

Is the carbon atom in CH2=CH-CH2-CH=CH2 coplanar?

Not coplanar, if conjugated diene such as 1,3-butadiene is coplanar