What do a helicopter s blader spin around ?

to make the air above to move at a higher velocity hence decreasing pressure

Explanation:

this is from Bernouli's principle

this creates an area of lower pressure above than below the helicopter hence the higher pressure below the helicopter makes it rise up

the answer is:

d. a story that frightened readers so much they would become suspicious of their surroundings

frankenstein is one of the terror novels wrote by the writers in a sort of bet, lord byron challenged them all to write a ghost story, and the story came to mary shelley in a dream, she wanted to conect with the fears of her society, fears of technology and changes, and she wanted readers to look around, freightened.

explanation:

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