3. Which statement about lines of longitude is true? a. They converge at the equator.
b. They converge at the poles.
c. They are parallel.
d. They locate positions in north and south directions.

Which would best keep the oxygen cycle stable? a. cutting down jungles to create farmland b. eliminating parks in large cities c. dumping toxic chemicals into the ocean d. reducing the amount of deforestation d. reducing the amount of deforestation