What is the structure of $CH_2 = C = CH_2$?

The number of $sp^2 - sp^2$ sigma bonds in the compound given below is

Which of the following can have a structure with $sp^3$ $C$ atoms only?

What is the proportion of $s$-character in $sp^3$,$sp^2$,and $sp$ hybrid orbitals? What is the order of electronegativity in it?

$sp^3d^2$ hybridization is not displayed by

Which of the underlined atoms in the molecules shown below have $sp$-hybridization?
$(u) H_2\underline{C}=CH-CH_3$
$(v) CH_2=\underline{C}=CHCl$
$(w) CH_3-\underline{C}H_2^+$
$(x) H-C \equiv C-H$
$(y) CH_3-\underline{C} \equiv N$
$(z) (CH_3)_2C=\underline{N}-NH_2$