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.
Psychologists must be registered/licensed with their Canadian provincial regulatory body or American state psychology board. Typically, it will take four years to complete an undergraduate degree in psychology, one to two years for a masterâs degree and, if required, another three to four years for a PhD.ou will need to first complete a four year undergraduate degree in psychology followed by graduate studies. Most university graduate programs require a four year undergraduate degree as an entrance requirement.