How long (in centimeters and years) was the Precambrian period to the rest of the scale?

Total length of Precambrian period is meter centimetres

Explanation:

Precambrian period has two major sub divisions  

a)Archean (oldest) and

b)Proterozoic

The length of Precambrian period would be equal to the sum of length of Archaean eon and the Proterozoic eon.

The length of Proterozoic eon  

Or

meter centimetres

The length of Archean eon meter cm

Total length of Precambrian period

centimetres

Or

meter centimetres

answer: 20 percent

the fish culture has become a developing commercial practice in developing countries which is already prominent in developed countries of the world. the major fish protein demand is being supplemented in developing countries is   fishing to meet the needs of the growing population. therefore, in some developing nations, the percentage of animal protein from fish in the diet can be as high as 20 percent.