Carnegie met tom scott his mentor when young andrew started working at age 12. why did he start working so young

Andrew Carnegie, the business magnate that developed the mighty American steel industry in late 19th century, was born in very humble circumstances. His family migrated from Scotland to escape poverty and then settled in Allegheny, Pennsylvania. There, he started working as a bobbin boy at age 13 for $1.20 a week. He worked at a very young age to pay debts incurred when migrating to America.

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d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.