Draw a $3$D representation of the molecule ketene, H$2$C$=$C$=$O$,$ using the following EXPLICIT instructions: sigma bonds in the plane of the paper are normal lines, sigma bonds or orbitals projecting in front of the page are heavy lines, sigma bonds or orbitals projecting behind the page are dashed lines, and pi bonds are shown by drawing the lobes of the p$-$orbitals and indicating the overlaps. What is the hybridization of each atom $($except H$)$ in this molecule?