Thus by 1803 there were two known rare earth elements, yttrium and cerium, although it took another 30 years for researchers to determine that other elements were contained in the two ores ceria and yttria (the similarity of the rare earth metals' chemical properties made their separation difficult).
For instance, students who pursue a Ph.D. in psychology usually take from five to seven years depending upon required coursework as well as internship and supervised residency requirements.
Before you can determine how long it will take you to earn your psychology degree online, you must identify what type of degree you want to earn. You can spend between 2 years and 8 years studying to earn a degree, and knowing which degree program will qualify you for your career choices is important. The time it takes to earn an Associateâs Degree in Psychology will take a lot less time than it takes to earn a Bachelorâs.