What are alkanes?

What are the various alkanes obtained due to insertion when 2-methylbutane reacts with singlet methylene ( :CH_(2)) ?

When R-Mg - X , Grignard's Reagent is treated with solvents can yield alkanes. . What is B ?

When R-Mg - X , Grignard's Reagent is treated with solvents can yield alkanes. . What is A ?

When R-Mg - X , Grignard's Reagent is treated with solvents can yield alkanes. . What is B ?

When R-Mg - X , Grignard's Reagent is treated with solvents can yield alkanes. . What is A ?

What are main natural source of alkane .

What would be the general formula for the molecular formulae of the members of the homologous series of alkanes ? What would be the value of 'n' for the first member of this series ?