I agree with you about 1, 2, 6, and 7.
I disagree about 3 (pay attention to the word "arid") and 4 (Google "Lusitania" to find out).
5 is probably correct, but check your text to be sure.
My answer: Mormon
2. The invention of the Blank Blank, made it possible for farmers to farm much bigger plots of land.
My answer: Mechanical Reaper
3. The practice of blank made it possible for farmers to grow wheat, despite arid climate.
My answer: reaper
4. The United states tried to stay out of World War I but was pulled in after a BLANK submarine sank British ocean liner and killed 128 American Civilians.
My Answer: Lusitania
5. The Depression years saw a reinvigoration of Utah's BLANK movement, and new laws passed allowing unions to protect workers' rights.
My answer: labor
6. Historians generally argue that BLANK<BLANK<BLANK pulled america out of the Great Depression, rather than President Roosevelt's New Deal Policies.
My answer: World War II
7. The United States was drawn into world war II after Japan attacked BLANK, Blank, killing 2,402 Americans wounding 1,282.
My answer: Pearl Harbor
I disagree about 3 (pay attention to the word "arid") and 4 (Google "Lusitania" to find out).
5 is probably correct, but check your text to be sure.
And remember that "text" doesn't always mean "book"! My granddaughter's texts through high school were all online, and not always in online book format.
I've never been able to find the name of that particular U-boat (Unterseeboot). I don't know if they had names or just numbers. But it was a German Uboat/submarine.
Of course, it could be other things, but the word "arid" in the sentence makes me think they want an answer related to how they watered crops in that climate.
https://eoimages.gsfc.nasa.gov/images/imagerecords/5000/5772/kansas_AST_2001175.jpg