Questions

We know that, elements in the same group of the periodic table have similar characteristics. Here magnesium and strontium are the same 2nd group elements and have same behavior. 

Therefore, strontium behaves same as magnesium. 

Haemophilia is an inherited bleeding disorder where the blood doesn't clot properly. It is caused when blood does not have enough clotting factor.

The main treatment for hemophilia is called replacement therapy. Concentrates of clotting factor VIII (for hemophilia A) or clotting factor IX (for hemophilia B) are slowly dripped or injected into a vein. These infusions help replace the clotting factor that's missing or low.

Polar lights (aurora polaris) are a natural phenomenon found in both the northern and southern hemispheres that can be truly awe inspiring.

Northern lights are also called by their scientific name, aurora borealis, and

Southern lights are called aurora australis.

Plant cell walls are mostly made up of the molecule cellulose. Cellulose is a polysaccharide, a complex sugar made of long chains of glucose.

The cell wall must be made of thick and strong material as it provides the structural shape of the plant and protection from insects and microorganisms.