The mute swan is a species of bird with an orange-reddish bill and white feathers. it is naturally found in europe and asia but can sometimes be found in the united states as a result of the importation of these non-native birds.

post-impressionism is a predominantly french art movement that developed roughly between 1886 and 1905, from the last impressionist exhibition to the birth of fauvism. post-impressionism emerged as a reaction against impressionists' concern for the naturalistic depiction of light and colour.

explanation:

answer; ///(b) it is composed of four protein chains and four heme groups;

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

•there must be variation for the particular trait within a population.

•the variation must be inheritable (that is, it must be capable of being passed on from the parents to their offspring).

•individuals with one version of the trait must produce more offspring than those with a different version of the trait.good

explanation: