What were people like Upton Sinclair who wrote about social evils and the abuses of child labor called?

Which region was almost every country colonized by an imperial power in the 19th century

Which of the following statements about this graph is accurate? world grain production has increased in every year since 1950. the amount of grain grown between 1950 and 1980 decreased. world grain production has generally increased between 1950 and 2010. more grain was grown in 1950 than in any other year.

What was a result of the use of farming machines