The Fischer presentation of $$D$$-glucose is given below.


The correct structure(s) of $$\beta $$-$$L$$-glucopyranose is (are) :

For "invert sugar", the correct statement(s) is(are)

(Given : specific rotations of (+)-sucrose, (+)-maltose, L-($$-$$)-glucose and L-(+)-fructose in aqueous solution are +66$$^\circ$$, +140$$^\circ$$, $$-$$52$$^\circ$$ and +92$$^\circ$$, respectively.)

The structure of D-(+)-glucose is

The structure of L-($$-$$)-glucose is

The correct statement(s) about the following sugar X and Y is(are)