Questions

Helium has the lowest freezing point of all the elements. When coming to metals, mercury has the lowest freezing point of all the metals.

About 150 - 200 species of plant, insect, bird and mammal become extinct every day or 24 hrs.

This is not an accurate but an estimation by U.N. Convention on Biological Diversity and Global Extinction Rates. It is also said that current extinctions were 'up to 100 times higher than the background rate.'

These are a couple of examples of things that retail staff may be expected to get involved with, and they'll be keen to see how much additional training they might need to provide.

Yes, Carbon disulfide is prepared by heating sulfur and charcoal. 

S2 + C ----> CS2

Spongy, porous bone tissue is also called cancellous bone.

Cancellous bone is found in bones that aren't generally under significant stress like in the shoulder blades, ribs, parts of the skull, and at the ends of long bones.

Here 6CO2 + 6H2O -----> C6H12O6 + 6O2 is the only option which best summarizes photosynthesis. We know that, photosynthesis is the reverse of cellular respiration in that carbon dioxide is used with water to form sugar, and oxygen is released.