Answer:
Option 5.
Explanation:
Many of the properties of water like high specific heat, cohesion, high vaporization heat, etc can be contributed to the polar nature of water molecule.
Water being a polar molecule as it contains positively charged hydrogen and an electro-negative oxygen which results in uneven or non uniformity in sharing of electrons which leads to dipole formation and hence polarization of the molecule due to which it attracts its neighboring molecules.
This polar nature imparts the properties like cohesion, surface tension , adhesion, etc due to the presence of hydrogen bonds in water molecule.
Answer:
(c) more than 500
Explanation:
Until 2019, more than 3000 planetary systems have been discovered that contain more than 4000 exoplanets, since some of these systems contain multiple planets. Most known extrasolar planets are gas giants equal to or more massive than the planet Jupiter, with orbits very close to its star.
It makes calculations with very large and small numbers easier.
Scientific notation is a system used in order to It makes calculations with very large and small numbers easier. It is useful as it allows very large number that would take a lot of space to write otherwise, and it allows them to be calculated easier. 
for example is a incredible large number, but written in this form is immediately understandable and useful for calculation.
