A subduction zone is where one tectonic plate is sliding under another one. It is not usually a continuous smooth motion, but an intermittent cycle of building pressure of one plate against the other and then a "slip" or movement that relieves the pressure by moving the plates. This movement is called an earthquake.<span />
The element found in period 4, group 2 is zirconium, Zr
1. The heart muscle cells need plenty of oxygen and nutrients so it needs its own blood supply.
2. The heart needs to have a blood supply to get ride of wastes.
Hope that helps. -UF aka Nadia
A is the answer to the question you have
