What common factor turned all four products into “hot” toys

from my own personal expirence food stamps has alot this makes it eaiser so we can affod bills and so we can life a better lifestyle not needing to worry about paying actual money to buy food since most people spend 100-300 dollars a month on food so this alot so we can afford other bills and other stuff we need

answer: in 1900, there were no "workplace safety laws"!

explanation: at the beginning of this century, workers in the united states faced remarkably high health and safety risks on the job.

a century ago in 1900 about three hundred out of every one hundred thousand miners were killed on the job each year.

[industria] developments occurred within a legal and regulatory climate that diminished employer’s interest in safety. as a result, americans developed production methods that were both highly productive and often very dangerous.