Explanation: I'd first address the issue as a whole and explain the meaning and the general impacts of climate change, then use a variety of different places. For example, global warming causes the ice caps to melt in Antarctica. Then, explain how this has an impact on the environment meaning that polar bears could be in life-threatening situations and possibly even become extinct in the future which has a further impact on other animals in that food chain and ecosystem. This is just one example. You could also explain the unbearable heat in countries nearer the equator, which prevent crops from growing; the sea levels rising; or extreme weather events like huge flooding or heatwaves. It depends what you have learnt about in class, but I'm assuming it would be about this sort of thing.
Mafic materials are usually dark in color and have relatively high specific gravities grater than 3.0 Felsic materials are usual at lighter in color and have specific gravities less than 3.0
