The tripeptide is written as Glycyl-Alanyl-Glycine. What is its correct structure?

The number of six-membered and five-membered rings present in norethindrone (a synthetic progesterone) are respectively:

Which of the following statements are correct?
a) In maltose,$C-1$ of one $\alpha-D$-glucose is linked to $C-4$ of second $\alpha-D$-glucose.
b) Quaternary structure of protein represents spatial arrangement of two or more polypeptide chains with respect to each other.
c) Nucleotide units in a nucleic acid are joined to each other through a phosphodiester linkage.
d) Abnormally low level of thyroxine leads to hypothyroidism.

Which of the following statement$(s)$ is(are) true?
$(1)$ Oxidation of glucose with bromine water gives gluconic acid.
$(2)$ The two six-membered cyclic hemiacetal forms of $D-(+)-$glucose are called anomers.
$(3)$ Hydrolysis of sucrose gives dextrorotatory glucose and laevorotatory fructose.
$(4)$ Monosaccharides cannot be hydrolysed to give polyhydroxy aldehydes and ketones.

Which of the following is water soluble?

How many isoprene units are present in abscisic acid?