(twenty points)
of the resources below, which one is perpetual?
fish
coal
timber
tidal energy

D. Tidal energy

Explanation - Resources generally get exhausted if used endlessly and in large quantity. Resources that cannot be replenished are called as non-renewable sources like coal. Perpetual resources are those resources that are present abundantly or less likely to get exhaust even when used endlessly.

They are also called as renewable source. Example of perpetual resources are solar energy, tidal energy etc. Fish if consumed in large quantities might get extinct in near future.  

you did not attach the discourse, but i assume it to be the discourse on the origin and basis of inequality among men (the original titile in french is: "discours sur l'origine et les fondements de l'inégalité parmi les hommes"), also know as "second discourse". in this discourse, jean-jacques rousseau emphasizes that private property is the basis of all inequalities.

therefore, what enabled the old regime to maintain as long as it did was private property.