<u>Answer:</u>
The correct answer option is C. 2.
<u>Explanation:</u>
We are given the number '0.0020' and we are to indicate the number of significant figures in the given measured number.
According to the rules of significant figures, numbers that are non-zero, zeros between any two significant numbers and the ending zeros in the decimal position are categorized as significant figures.
Since there is one non-zero number and one ending zero in the decimal position, therefore 0.0020 has 2 significant figures.
Answer: 
Explanation:
Electron gain enthalpy is defined as energy released on addition of electron to an isolated gaseous atom.
The amount of energy released will be maximum when the tendency to attract electrons is maximum. As flourine has atomic number of 9 and has electronic configuration of 2,7. It can readily gain 1 electron to attain stable noble gas configuration and hence liberates maximum energy.
Answer: The elements that have the lowest electronegativity are the VIII A elements or noble gases. These elements have a theoretical electronegativity of zero. These elements are stable in their electron configuration there is not force moving the noble gases to gain any electrons.
Explanation:
