How does distance from the epicenter of an earthquake change the earthquake's effects?

Mario performed an experiment to determine if photosynthesis was affected by the amount of light that a plant received. what could he have done to increase the validity of his data? reduce the number of plants. remove the 1 hour group. add a 0 hours control. measure the oxygen in liters

What did the first language sound like

How can antibodies "remember" a particular bacterial invader or "antigen" on that invader?