Which of the following flows through ecosystems in one direction? 1. Water
2. Energy
3. Nitrogen
4. Carbon

How are isotopes of the same chemical element alike? how are they different?

The earth's surface is (science) a: studied using seismic waves b: constantly changing over time c: only studied indirectly d: the same today as million of years

Which of these describes the rate of this chemical reaction? h2 + cl2 → 2 hcl a. an increase in the concentration of hcl and h2 with time b. an increase in the concentration of hcl with time c. an increase in h2 and cl2 with time d. a decrease in hcl and cl2 with time