8. the time period of artificial satellite in a circular orbit of radius r is t. the radius of the orbit in which time period is 8t is: (b) 3r

Explanation:

It is given that,

The time period of artificial satellite in a circular orbit of radius R is T. The relation between the time period and the radius is given by :

The radius of the orbit in which time period is 8T is R'. So, the relation is given by :

So, the radius of the orbit in which time period is 8T is 4R. Hence, this is the required solution.  

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

the answer would be b i believe