What MOSTLY determines the chemical properties of the atoms of an element?

A) proton number
B) neutron number
C) electron number
D) valence electron number

An engineer decides to use a slightly weaker material rather than a stronger material, since she knows that the stronger material can break suddenly. this is an example of what? a choosing a material that will show warning before it fails b using composite materials that combine strength c using a material for multiple applications d using design techniques that increase efficiency and reduce cost