Which of the following features are common to all trna molecules? each is a single chain with between 73 and 93 ribonucleotides. they contain many unusual bases. about half the nucleotides are base-paired. they usually have a pg at the 5' terminus. all of the above.

The changes to agriculture in the united states since 1900 is that increased mechanization has increased food production, thereby increasing the need for labor. there has been an increased need for higher speeds of food production due the fact that the population in the united states continues to rise.