Which of these statements is true about the oxygen revolution?

Which of the following elements does soil need in the largest quantities to sustain plant life? a. copper b. iron c. nitrogen d. zinc

What does all of the organ system in a human form

My question says on my assignment. read the following scenarios and decide which of the properties of life are being described. the first one is. katherine stopped on the way to school to grab some donuts. 2. because a dog cannot sweat, it has to pant in order to stay cool. 3. an elephant trun had no bone but 4,000 muscles. i have no idea what i am supposed to anwer. i can't find the answer in my notes or book that i can understand anyway