Calculate the relative molecular mass of the following compound. 
Lead sulphate
(Given, atomic masses of various elements, $\mathrm{Ca}=40\mathrm{u}$, $\mathrm{S}=32\mathrm{u}$, $\mathrm{O}=16 \mathrm{u}$, $\mathrm{Pb}=207 \mathrm{u}$)

Calculate the relative molecular mass of the compound. 
Calcium phosphate

(Given, atomic masses of various elements,$(\mathrm{Ca}=40\mathrm{u}, \mathrm{O}=16\mathrm{u} \mathrm{and} \mathrm{P}=31\mathrm{u})$

Chemical formula of glucose is represented as _____.

(A) ${\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6$                (B) ${\mathrm{C}}_{12}{\mathrm{H}}_{22}{\mathrm{O}}_{11}$                (C)${\mathrm{C}}_5{\mathrm{H}}_{10}\mathrm{O}$

Enter your correct answer as A, B or C.