When it gets cold, the accumulated water inside the pipes freezes, expands and creates extreme pressure.
Answer:
3. B, D
Explanation:
A primary source is an animal that eats only plants. (herbivore) A secondary source is an animal that only eats herbivores (carnivores)
B has birds; which are food for carnivores, and fruits, nuts, and blossoms; which are food for herbivores.
D has vegetables and grains; which are food for herbivores, and meat; which is food for carnivores
The other options have only food for carnivores, or only food for herbivores, so the answer is 3
The correct option is INTRODUCTION OF EXOTIC SPECIES;
Exotic species refers to an introduced specie of an animal which is alien to the ecosystem in which it found itself and which has been transported to that ecosystem either intentionally or by accident. Exotic species normally have varieties of effects on the ecosystem to which they are introduced, sometimes the effect will be good and sometimes the effects could be devastating depending on the particular situation.
Factors which promote diversity include: larger size of the ecosystem, longer growing seasons and climatic stability.<span />