Answer:
Start with something that will grab your audiences attention like a rhetorical question (do you want to kill this planet) or a dramatic statement (we are leaving this planet to our children so what are we going to do about it)
And end with something that leaves the reader/audience speechless and wanting to help and unite against a common enemy (along the lines of the above but more like (we are leaving this planet to our children so what are we going to do about it)
Hope this helps let me know if you need anything else! :)