What concerns might the
use of biotechnology raise
for people? For other
organisms?

Spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

Select the word from the list that best fits the definition a system made of 25 satellites

The earths core is made up mainly of what 2 substances? 2. like an egg, earth has a core, a layer surrounding the core, and a thin, hard outer layer. which layers of the earth match the layers of an egg?