I got A, -32, but it has been awhile since I have learned this in my math class. You might want to wait for someone else to verify this answer.
Answer:
72 N
Step-by-step explanation:
From the question.
Force is directly proportional to acceleration, with the mass of the object constant.
F α a
F = ka
F₁/a₁ = F₂/a₂....................... Equation 1
Where F₁ = Initial force, a₁ = initial acceleration. F₂ = final force, a₂ = Final acceleration.
make F₂ the subject of the equation
F₂ = (F₁/a₁)a₂................ Equation 2
Given; F₁ = 64 N, a₁ = 8 m/s², a₂ = 9 m/s²
Substitute these values into equation 2
F₂ = (64/8)(9)
F₂ = 72 N
Answer: Choice A) 8.742 * 10^7
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Work Shown:

Extra info:

which is a little over 87.4 million
Answer:
has 3 significant figures
Step-by-step explanation:
because zeros are counted if they are between the numbers
Answer:
x = 
Step-by-step explanation:
Given
x -
= 
Multiply through by 10 ( the LCM of 5 and 10 ) to clear the fractions
8x - 1 = 3 ( add 1 to both sides )
8x = 4 ( divide both sides by 8 )
x =
= 