Questions

Electronegativity measures an element's ability to form chemical bonds. Helium is the most electronegative element followed by Fluorine.

Here in the given options, Oxygen is the most electronegative element. Fluorine is followed by Oxygen, Chlorine and Nitrogen is the most electronegative elements list.

Competition  occurs when two or more organisations act independently to supply their products to the same group of consumers.

There are mainly two cases when firms can compete. One is price where firms are selling identical or very similar products, they must compete on price with each firm trying to undercut the others. The other is differentiation. A non-price competition depends on making a product different from those of competitors and by giving it distinctive qualities that are valued by the target market. This might include branding, styling, special features or higher levels of customer service. Good competition provides more options to customers and also brings with it improved  customer services.

Rights guaranteed by law, is the best description of Civil liberties.

Civil liberties are also called as personal freedoms. They are personal guarantees and freedoms that the government cannot abridge, either by law or by judicial interpretation, without due process.

This is a layer of atmosphere about 60 to 70 km above the earth and extends to about 400km. It contains ionised particles which can reflect radio waves making radio communication round the world possible.

Nankana Saheb

The Doppler effect or Doppler shift is the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source.