For this case we have that according to the order of algebraic operations PEMDAS, the multiplications have priority over the addition and subtraction, then, we have the following expression:

Thus, the value of the expression is 1000.
Answer:

80 inches, diameter is twice radius
A. He feels tired and sick because the focus on the mechanical measurements of stars is not satisfying to him.<span>
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Step-by-step explanation:
- volume of cylinder=90π
- πr²h=90π
- 3²h=90
- 9h=90
- h=90/9
- h=10
hope it helps.
Remember PEMDAS
Do parentheses, results in 25. So whats left is 87-25*(-3)+9
Then you multiply -25 by -3, answer is 75. 87+75+9
Add all of them up. 171
The answer is 171!