Umm, you just need to write about how economic growth needs to be kept within the target economic growth range (3-4%). This helps to sustain the environment by not producing excessive amounts of negative externalies and does not consume as many non-renewable resources. this helps promote intergenerational equity. also just write how renewable resources can not be consume excessive as if too many are consumed then they may become non-renewable as there isnt any time for them to reproduce.
Hope this helps