What is it called when u plow across the slope of hills

Which statement is true about the cell theory? a) it is well-supported by evidence. b) it is unchangeable and permanent.

Which of these resources is used worldwide to make construction products, pottery, and porcelain

The finches on the galapagos island were similar in form except for variations of their beaks. darwin observed that these variations were useful for: attracting a mate defending territory building nests gathering food