What could a human living now and a horse living thousands of years ago have i'm common

Aperson with age is more likely to catch diseases that healthy people usually don’t catch. what are these infections called?

Several billion years ago which gas was the least prevailant in the atmosphere

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.