Answer:
Speed of comet before collision is

Explanation:
Correction: (As stated after collision comet moves away from moon so velocity of moon and moon and comet must be opposite in direction. as spped of moon after collision is −4.40 × 10^2km/h so that comet's must be 5.740 × 10^3km/h instead of -5.740 × 10^3km/h)
Solution:

Case is considered as partially inelastic collision, by conservation of momentum

Answer:
The current flow occurs due to the difference in electrical potential
Explanation:
The difference in electrical potential between two point in electrical circuit causes charges to flow, usually from the region of higher potential to the region of lower potential. The flow of these charges is known as current.
Thus, the current flow occurs due to the difference in electrical potential. Electric potential means work done in moving a unit positive charge from infinity to a particular point in the field against the electrical resistance of that field.
Bacteria can be used to grow a lot of vaccines. new, stronger bacteria has evolved that are resistant to antibiotics. Diabetics have a steady supply of inexpensive insulin
Soil is the result of chemical or physical weathering of a parent rock .this is so since the soil is just tiny particle of the huge parent rock and hence it affects soil composition<span> .</span> if the parent rock was made of limestone then the soil composition will constitute calcite<span> and </span><span>aragonite mineral elements from the limestone parent rock.</span>
Slow down significantly before the curve in the road