Chapter 2 - Structure and Properties of Organic Molecules - Problems - Page 55: Problem 2-3 a

$C_1$ Hybridization: $sp^3$ Geometry: tetrahedral Bond Angels: 109.5 $C_2$ Hybridization: $sp^2$ Geometry: Trigonal Planar Bond Angels: 120 $C_3$ Hybridization: $sp^2$ Geometry: Trigonal Planar Bond Angels: 120 $C_4$ Hybridization: $sp^3$ Geometry: tetrahedral Bond Angels: 109.5

The $C_1$ and $C_4$ have four domains (four single bonds with H) around them. Thus, it's tetrahedral and tetrahedral geometry has 109.5 degrees angels. The $C_2$ and $C_3$ have three domains (two single bonds and one double bond) around them. Thus, it's trigonal planar and trigonal planar geometry has 120 degrees angels.