Answer:
Hope the below helps!
Explanation:
Greenhouse gases (such as methane, carbon dioxide etc) have lots of vibrating particles. These molecules eventually release radiation, which travels up Earth's atmosphere (because warm air rises), is trapped and adds to the greenhouse gas effect.
Oxygen and nitrogen don't interfere with infrared waves in the atmosphere. That's because molecules are picky about the range of wavelengths that they interact with.
I have attached a diagram that shows the greenhouse effect. It might help to visualise this.
Exotic species do not have a niche in the ecosystem that they are in. Therefore they take up resources that native species rely on to survive. Exotic species also have no natural predators in that environment causing them to flourish and multiply quickly.