The light intensity can be measured by

What does the density of water depend on?

Match the following columns:

Column-$I$ (Temperature)	Column-$II$ (Habitat)
$P$. Sub-zero levels	$I$. Thermal springs
$Q$. Can exceed $50^{\circ}C$	$II$. Polar regions
$R$. Can even exceed $100^{\circ}C$	$III$. High altitude areas
	$IV$. Deep-sea hydrothermal vents
	$V$. Tropical deserts

In which of the following habitats does the diurnal temperature of the soil surface vary the most?

Which of the following factors collectively determine the percolation and water-holding capacity of soils,along with parameters like $pH$,mineral composition,and topography?

...... is the most ecologically relevant environmental factor.