Which of the following factors are common to all organisms?

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

When listening the levels of orginization in orginisims from the smallest to most complex , which level is just below organs in complexity

What is any method of measuring the age of an object or event in years, such as using atomic half-life?