What is the mainimum thickness of aluminum foil to block alpha particles emitted from cf- 252 source?

An architect plans to use solar energy to heat the next house he designs. what principle of absorption and infrared energy can be applied to the design of the new house? how could she apply to those principals?

What are the dimensions of the cross section that passes through the points a, f, g, and d?

Which is a substance that can be separated by physical means and is not the same throughout