Answer:
C
Step-by-step explanation:
First we find the z-score.
z = (x - μ) / σ
z = (520 - 500) / 60
z = 0.33
Using a calculator or z-score table:
P(z < 0.33) = 0.6293
The probability is approximately 63%. Answer C
Answer:
correct answer is 406/25+a10
Step-by-step explanation:
Answer: 
<u>Step-by-step explanation:</u>

NOTE: The sign between 4x and 7 is missing in the question you posted. I assumed it was 4x + 7 in order to solve the equation.
Answer:
its the second one
Step-by-step explanation:
hope it helps