How many of the given compounds will give a positive Biuret test ____________ ?

Glycine, Glycylalanine, Tripeptide, Biuret

In a linear tetrapeptide (Constituted with different amino acids), (number of amino acids) $-$ (number of peptide bonds) is ________.

From the vitamins $\mathrm{A}, \mathrm{B}_1, \mathrm{~B}_6, \mathrm{~B}_{12}, \mathrm{C}, \mathrm{D}, \mathrm{E}$ and , the number of vitamins that can be stored in our body is _________.

The separation of two coloured substances was done by paper chromatography. The distances travelled by solvent front, substance A and substance B from the base line are 3.25 cm, 2.08 cm and 1.05 cm, respectively. The ratio of R_f values of A to B is _____________.

Optical activity of an enantiomeric mixture is $+12.6^{\circ}$ and the specific rotation of $(+)$ isomer is . The optical purity is __________.

The spin only magnetic moment of the complex present in Fehling's reagent is __________ B.M. (Nearest integer).

The denticity of the ligand present in the Fehling's reagent is ___________.

Vanillin compound obtained from vanilla beans, has total sum of oxygen atoms and $\pi$ electrons is __________.