Suppose that a group of 1000 orange trees is laid out in 50 rows of 20 trees each. To determine the sugar content of fruit from a sample of 30 trees, researcher A suggests randomly selecting five rows and then randomly selecting six trees from each sampled row. Researcher B suggests numbering each tree on a map of the trees from 1 to 1000 and using random numbers to select 30 of the trees.

Which selection method is preferred if it is known that all the trees and rows are homogeneous?

Researcher A's method is preferable because it is easier to implement.

Researcher B's method is preferable because it produces a simple random sample.

Both procedures are equally good.

Neither method is suitable.

Which selection method is preferred if it is known that different parts of plantation may vary one from another?

Researcher A's method is preferable because it is easier to implement.

Researcher B's method is preferable because it produces a simple random sample.

Both procedures are equally good.

Neither method is suitable.