the use of pesticides on crops has been a common farming practice for decades. what had been the greatest effect of natural selection through the use of pesticides on certain insect populations?

What do isotopes of uranium have the same number of? what do they have a different number of? a) same number of protons; different number of electrons b) same number of protons; different number of neutrons c) same number of electrons; different number of protons d) same number of neutrons; different number of protons