Explain why a diagram of the tree of life is difficult to construct. ​

Which of the following is not a way in which a vascular plant's xylem and phloem are similar?

In order to clone adult animals, scientists typically begin with a(n)

Which statement about relative potential energy of electrons is correct? a. an electron in the 2 p orbital of the second electron shell has more potential energy than an electron in the 2 s orbital of the second electron shell. b. an electron in the 2 p orbital of the second electron shell has more potential energy than an electron in the 3 p orbital of the third electron shell. c. an electron in the 3 p orbital of the third electron shell has more potential energy than an electron in the 2 p orbital of the second electron shell.