Fish have scales that enable them to live in a water environment. this is an example of

Adaptation

Explanation:

Adaptation of fishes to the aquatic (water) habitat requires that they have the following:

- Scales, the hardened pigment that covers the skin of fishes and some other animals.

- Gills, the organ used by most fishes to breathe under water.

Other include tail, fin (dorsal, pelvic) etc. All these help the fish to adapt to the water environment.

linnaeus is the father of taxonomy, which is the system of classifying and naming organisms. one of his contributions was the development of a hierarchical system of classification of nature. today, this system includes eight taxa: domain, kingdom, phylum, class, order, family, genus, and species.

energy per photon is e = h*c / λ  

e = 6.63*10^-34 * 3*10^8 / 6*10^-7 j = 3.315*10^-19 j  

nr. of photons = 10j / 3.315*10 = ^-19 j per photon = 3.02*10^19 photons