Answer:
Shark skin has been used by many cultures as sandpaper. It's kept shipmates safe in slippery-when-wet conditions. Swimsuits modeled on shark skin are said by Speedo to reduce drag by up to 4 percent. Now, research by two separate groups could lead to synthetic shark skin that would make ships and submarines faster and less expensive to operate.
Answer:
Option A
Explanation:
Options -
A-avoid water pollution.
B-build thermal power plants.
C-add water features to gardens.
D-avoid drip irrigation systems
Solution -
The largest source of freshwater on planet earth is underground water. The water beneath the surface of earth is very limited. The total fresh water reserve on earth is 3% of the total water on earth. Pollution due to discharge of waste water into the rivers and oceans has caused the degradation of not only surface water but also ground water.
Thus, option A is correct
Drip irrigation is a means to prevent wastage of water during irrigation. Thus, avoiding it will cause further loss of fresh water.
Addition of water feature will increase usage of water, thus it is also incorrect
Building thermal plant will also cause water pollution and wastage. Hence, option B is also incorrect
It’s called Igneous .......................
A. They impede fish migration and spawning
Answer:
Nucleic acid don not contain amino acids.
Explanation:
Nucleic acid is primarily composed of three main components, pentose sugar, phosphate group and nitrogenous bases. Amino acid is the building block of proteins.