1. read "what triggers ice ages? " briefly describe what you think the world would be like if the amount of greenhouse gases in the atmosphere were reduced to levels like those during the ice age.

I think the would would not have as many people on it as the ice age and technology wise we wouldn't be as advance as we are now but i do think like if the drop of green house gasses were sudden after time the human race would very slowly get back to maybe half the current population. if that makes any since   

Ithink the answer is d.

Generally travels west to east but often shifts to north and south