What are the characteristics that are essential to ensure survival of any organism

Ronald wants to see if a new shower cleaner works better in removing soap than his old cleaner. he uses the new cleaner on one half of the shower tiles and his old cleaner on the other half. identify the independent and dependent variables in this experiment. enter your answer in the space provided.

Several billion years ago which gas was the least prevailant in the atmosphere

Using meiosis, the sporophyte produces spores that are .