Which of the following is considered to be the only natural permanently magnetized material?
alnico
lodestone
magnetite
iron

The correct answer is "lodestone".

Explanation:

Lodestone is a naturally occurring magnet comprised of a magnetized form of magnetite. Its name come from the term "leading stone" because it was first used for navigation purposes to create magnetized iron that was used as a magnetic compass. Lodestone is permanently magnetized and is the strongest magnet found in nature.

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation: