Which of the following is not true about a nuclear power plant? they produce fewer carbon emissions than a coal-fired power plant. they are a relatively minor contributor to the usa's energy demands. they produce radioactive waste that must be safely stored for many years. they can explode like a nuclear bomb.

Nuclear power contributes a significant percentage of electricity in the USA. 20% of USA electricity generation is by nuclear power plants. This is the second biggest energy source in the United States after fossil fuels.  

The biggest challenges that are posed by nuclear energy is safety and radioactive waste. Nonetheless, nuclear power is among the cleanest energy sources on the planet in terms of emissions.

answer; i believe the correct answer is (solid gold);

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."