Why does the earth's co2 level go up and down every year?
1.because the leaves in the fall die and fall off releasing carbon dioxide and performing
less photosynthesis allowing for more carbon dioxide in the atmosphere
2.we don't know
3.because the leaves in the spring and summer contribute to photosynthesis removing
more carbon dioxide

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.