A copper block (20°C) is placed in contact with a lead block (30°C), which is already in contact with an iron block (70°C). What will happen in this situation?

Heat will flow from the iron to the lead and from the lead to the copper until the temperatures are equal.

Heat will flow from the copper to the lead and from the iron to the lead until the temperatures are equal.

Heat will flow from the copper to the lead to the iron until the temperatures are equal.

Heat will flow from the lead to the copper and to the iron until the temperatures are equal.

Which statement is a reason to support population regulation? a) it is unethical for us to control birth control rates b) humans have the freedom to produce as many children as desired c) the gap between the rich and poor has been narrowing since 1960 d) billions more people on the earth will intensify many environmental and social problems

Achemical reaction (also known as a chemical change) produces substances that are chemically different from the starting materials. an example of a chemical reaction is the formation of water from hydrogen and oxygen gas.in a physical change, a substance changes its physical appearance but not its chemical identity. an example of physical change is the formation of liquid water from solid water, a familiar process called melting. physically, liquid water looks very different from solid water (ice) but the chemical identity, water, is the same for both. which of following changes that affect the composition of our atmosphere involve physical changes and which involve chemical reactions? oxygen gas changes to ozone during thunderstorms carbon dioxide is produced by the combustion of gasoline in an automobile engine. when coal, oil, and natural gas are decomposed in landsills they produce methane gas. freezing rain develops when a warm air mass overrides a cold air mass. fog forms from water vapor when the temperature drops below the dew point

How have the greenhouse gasses increased from the year 2000 to 2018