The answer is D. because that makes more sense
Air pressure is measured with a barometer.
when an optical telescope located on the ground is used to view the sky the image has to surpass through the earth's atmosphere which is polluted. so the resolution wont be clear. When viewed on a mountain top both optical and infrared telescopes would perform better as the air above the atmosphere is less depth and cleaner.
Answer is (4) - Se.
Among the given choices Se has the highest electronegativity value as 2.4 compared to others. Hence, Se shows <span>greatest attraction for electrons in a chemical bond.
</span>Electronegativity is
a value that tells us how an atom can attract electrons towards itself. <span>If
the electronegativity is high, then the attraction to the electrons is also high.
</span>