6 Mark question Evolution of the atmosphere

MTD. Make a model answer for this question in your books

 has increased overall

 decreased overall

 water vapour has overall

 carbon dioxide small increase over last years

Explanations

 carbon dioxide decreased due to and oxygen increased due to

(carbon dioxide + water -> sugar + oxygen in the presence of light)

 water vapour to form the oceans

 carbon dioxide in the oceans

 carbon dioxide formed rocks (limestone)

 carbon dioxide formed fossil

 carbon dioxide increased by activity

 carbon dioxide increased from burning of fuels