Portland, Oregon, is a city right next to northern west coast of the USA. Besides being very close to the sea, it is also laid on a river. The sun that heats up the ocean and the river leads to evaporation, causing water vapour to ascend, because of a few wind currents, this water vapour is taken to Portland's area where it colds down and condensates, raining over Portland.
Answer:
This process is called genetic engineering.
Other than contributing to potential increase in diversity of species in an ecosystem, exotic species have positive benefits like removing toxins from the soil, regulating erosion, and controlling undesirable species.
I believe you use the pH scale with comparing acids and bases.
