What number should be added to 77 to make the sum 0?   77  –77  0  –76

Compounds which are found naturally in the earth are called: a. ores b. composites c. rocks d.minerals

Read the article about the fraser river, one of the most important rivers in canada. what is the most important species of fish in this river? why are the numbers of these fish declining?

Hurricanes a. usually form over land b. usually intensify over land c. gain strength from ocean heat d. usually form over the poles