Two forms of $D$-glucopyranose are obtained from the solution of $D$-glucose. What are these called?

$L$-isomer of tetrose $X$ $(C_4H_8O_4)$ gives positive Schiff's test and has two chiral carbons. On acetylation,$X$ yields triacetate. $X$ also undergoes the following reactions:
$X$ $\xrightarrow{HNO_3} A$ $\xrightarrow{NaBH_4} \underset{\text{Chiral compound}}{B}$
$X$ is $.......$.

Write a note on Disaccharide compounds.

Which of the following sugars is present in the nucleotide of $RNA$?

Which examples of carbohydrates exhibit $\alpha$-link,($\alpha$-glycosidic link) in their structure?

What is the product obtained when $Br_{2}$ water reacts with glucose?