A. Earth worms
Because it can only flow one way
Answer:
controlled experiments
Explanation:
Experiments in which all variables are identical except for one are called controlled experiments. This where an observer tests his hypothesis by looking on changes that were brought about by one variable. The results are always dependent on one adjusted variable.
Answer:Oxygen
Explanation: During cellular respiration, glucose is broken down in the presence of oxygen to form carbon dioxide, water and energy. Glucose + oxygen --> carbon dioxide + water + energy.
The balanced chemical equation for cellular respiration is C6H12O2 + 6O2 --> 6CO2+ 6H2O + Energy
Explanation:
New ocean crust is formed at the mid ocean ridges. The new crust is then pushed away from the ridge as newer crust comes to the surface. The ocean crust then spreads out enlarging the ocean. The farer away from the ridge the ocean crust is the older the crust