Which vitamin is excreted through urine in higher vertebrates?

Describe the role of liver,lungs,and skin in excretion.

What is the composition of sweat produced by sweat glands?

Which of the following pairs is correct?

Workers working in deep mines usually face dehydration because...

Components present in sweat $- P$
Components present in sebum $- Q$
$I -$ Sterols,$II -$ Waxes,$III - NaCl$,$IV -$ Hydrocarbons,
$V -$ Lactic acid,$VI -$ Small amounts of urea
Select the correct option for $P$ and $Q$.
$P \quad Q$