D. Organisms only need water
Transport of a compound across a cell membrane (down a concentration gradient) was measured at several concentrations. The presence or absence of ATP had no effect on the transport of this compound. ... Why are the lipid bilayers in cells called "selectively permeable"? They are permeable to some substances but not others.
D, a sonic boom is only produced when a body is traveling faster than sound
Answer:
A
Explanation:
Tilling agitates the topsoil and removes ‘unnecessary’ vegetation so the main crop can grow without competition. Tilling improves soil aeration and drainage for plants to grow well. Nonetheless, it can lead to other consequences such as soil erosion because it loosens the soil and makes it easy to be carried away by wind and water.
