Caroline loves bubble gum. Her teacher gives bubble gum to every child who finishes their math facts work sheet in less than one minute. Caroline never finishes in one minute, and she cries when everyone gets bubblegum except for her. The faster she writes her answers, the more mistakes she makes. The most likely reason for the reinforcer not working is

Restricted range of options

Explanation:

In simple words, the restricted range of options given to Caroline is the main reason behind her reinforce not working. She has given a specified time under which she has to perform a specified task. Thus, there is no other way for her to achieve satisfaction is her performance and due to less efficiency in the given option she is feeling nervous an dull.  

industry had made the u.s. the richest nation in the world at this time. the second industrial revolution caused growth in industry and transportation, which allowed increased trade between nations.

answer; i believe the correct answer is (8) eight.