The correct answer is B) Treaties expanding International Trade
After the second world war, the world has gradually opened up to one another for trade and opportunities.
We see that in the development of the World Trade Organization, as well as the NAFTA (North American Free Trade Agreement) between Canada, US, and Mexico and probably the most successful example in the European Economic Zone.
Some plants cant survive.
Energy and matter characterize both physical and biological systems. These systems are defined both by the types of energy and matter they contain and by how that matter and energy move through and between systems. ... This means that energy and matter can change forms but cannot be created or destroyed.
Photosynthesis, how plants survive. Sunlight is absorbed.
Answer: Possession of Valves
Explanation: Veins possess valves which ensures that blood flows in only one direction. Valves helps blood to flow back to the heart against gravitational force.
Arteries don't have valves because the pressure originating from the heart is capable of causing the blood to flow in one direction.