Which is the weakest among the following types of bond?

Which of the following compounds forms the maximum number of hydrogen bonds?

The dominant intermolecular force that must be overcome to convert liquid methanol to its vapour is

In ice,the length of $H$-bonds:

Maximum number of hydrogen bonds in $H_2O$ is

Viscosity of a liquid arises due to strong intermolecular forces existing between the molecules. Stronger the intermolecular forces,greater is the viscosity. Name the intermolecular forces existing in the following liquids and arrange them in the increasing order of their viscosities. Also give reason for the assigned order in one line.
Water,hexane $(CH_3CH_2CH_2CH_2CH_2CH_3)$,glycerine $(CH_2OHCH(OH)CH_2OH)$