What are $\beta - D - \text{glucose}$ and $\beta - D - \text{galactose}$ known as in relation to each other?

The structure of $D-(+)$-glucose is given. What is the structure of $L-(-)$-glucose?

Four carbohydrates: glucose,lactose,sucrose,and starch are present. Different tests are carried out with these $4$ carbohydrates separately. The following observations are made:
$(a)$ Heated: It is charred.
$(b)$ $I_2$ solution: No violet colour.
$(c)$ Fehling solution: Reddish brown precipitate is observed.
$(d)$ It does not reduce copper$(II)$ acetate to $Cu_2O$. No red precipitate is observed in $5 \ min$.
Which carbohydrate satisfies all the above observations?

How many moles of acetic acid are obtained in the reaction when one mole of glucose is treated with excess acetic anhydride (in $moles$)?

If a monosaccharide contains an aldehyde group,it is known as:

$L$-isomer of a compound $A$ $(C_{4}H_{8}O_{4})$ gives a positive test with $[Ag(NH_{3})_{2}]^{+}$. Treatment of $A$ with acetic anhydride yields a triacetate derivative. Compound $A$ produces an optically active compound $B$ and an optically inactive compound $C$ on treatment with bromine water and $HNO_{3}$ respectively. Compound $A$ is ....