Answer:
It is an observational study
Explanation:
In an observational study, nothing changes, all the researcher has to do is to record findings, it is a study that involves the collection of data in a real-world setting without intentionally manipulating any variable. On the contrary, an experimental study involves the manipulation of variables, you have the control group and the test group, the test group is subjected to the treatment.
Answer:
Are you asking for my opinion?
Explanation:
The government had to spend money for supplies for the military so economic changes for civilians were very real
Carnegie's early job with the railroads helped him predict that the demand for steel to build railroad tracks and bridges would grow.