Questions

A graph that describes the maximum amount of one good that can be produced for every possible level of production of the other good is nothing but a production possibilities curve.

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. 

Jay Cooke & Company, a major component of the United States banking establishment, found itself unable to market several million dollars in Northern Pacific Railway bonds in september 1873. Cooke's firm, like many others, had invested heavily in the railroads.

Hence, the bankruptcy of Jay Cooke & company initiated the Panic of 1873.

Black

Matching blood group before marriage is important. This is to prevent Rh incompatibility. Rh incompatibility can lead to erythroblastosis fetalis (Hemolytic disease of the newborn-HDN). Fetal RBC gets destroyed & newborn may get severe anaemia, jaundice. This jaundice is more severe than Physiological jaundice ( which is the most common and will usually resolve on its own).

In very severe form, a fetus may die due to heart failure. This is mediated by the antigen-antibodies reaction. Transfer of maternal antibodies across the placenta occurs. This happens when Rh +ve man marries Rh-ve lady.

So Rh +ve man should try to avoid marrying Rh-ve lady.

Matching blood groups for marriage ::

Boy : A = Girl : A & AB 

Boy : B = Girl : B & AB 

Boy : O = Girl : O, A, B & AB 

Boy : AB = Girl : AB 

Boy : Rh+ve = Girl : Rh+ve 

Boy : Rh-ve = Girl : Rh+ve & Rh-ve.

Blood groups that do not match for marriage ::

Boy : A = Girl : O & B 

Boy : B = Girl : O & A 

Boy : AB = Girl : O, A & B 

Boy : Rh+ve = Girl : Rh-ve.

House of representatives has the power of impeachment in the office.

Phosphorescence is a phenomenon associated with an algal division called euglenophytes. 

Phosphorescence is a phenomenon when an object is capable of releasing photons of light at a longer wavelength in response to absorbing light of a shorter wavelength. The object releasing the light only releases the light after some time has passed since it absorbed the light of a short wavelength.

Euglenophytes are single-celled plant-like protists that have no cell wall.