Apaleontologist is most interested in which two parts of the earth system

The biosphere and lithosphere, because paleontologist are interested in the history of the evolution of life. The lithosphere is the outer most crust and mantle, and the biosphere is where animals (such as humans) and plants mostly reside, both of which are spheres where artifacts and clues to the past are mostly found.

Answer : option a) 84explanation :

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.

#2- the hno3 has a h+ ion and the naoh has an oh- ion