Where is lead contamination mainly occur

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

Consider the elements bromine and chlorine; which elements has a larger ionic radius ?

The melting point of sulfur is 115 °c and its boiling point is 445 °c. what state would sulfur be in at 200 °c?