A student is studying which fertilizer/soil will produce the tallest tomato plants. She will use regular dirt, Miracle Gro, Dr. Dirt, and sand mixed with nitrogen. She will use all the same species of tomato and the same pot. She plans on watering the plants equally and exposing them to the same levels of sunlight for 4 weeks. . What is the independent variable?

the answer would be the different soils she is using

i think that you are smart and you should fit for it out

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.