Questions

Half the Product of Number in the upper & lower box gives the number in the middle box.

i.e. 18 x 4/2 = 36

15 x 6/2 = 45

In the same way 

8 x N/2 = 44 => N = 11.

Breaking of relationships is prevented once referential integrity on a database is enforced

Stratification as actually the settling down of sediments with different properties to form layers/strata over years. Stratification especially occurs on the bed of water bodies such as oceans.

Stratified sedimentary rocks are used to study the ecological conditions over previous years/eras.  

The other choices like Windstorms, Glacial Ice and Stream water are mediums which sediments are transported.