Complete Question
The complete question is shown on the first uploaded image
Answer:
The calcium level that is the borderline between low calcium levels and those not considered low is 
Step-by-step explanation:
From the question we are told that
The mean is 
The standard deviation 
The proportion of the population with low calcium level is
5% = 0.05
Let X be a X random calcium level
Now the P(X < c) = 0.05
Here P denotes probability
c is population with calcium level at the borderline
Since the calcium level is normally distributed the z-value is evaluated as

The critical value for 0.05 from the standard normal distribution table is

=> 
substituting values

=> 
=> 
The answer is: 90° .
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Answer:
a = 4h.
Step-by-step explanation:
Area (a) = base (b) * height (h).
When h = 2, a = 8:
a = bh
6 = 2b
b = 4
The result 4 is the same for h = 5, 7 and 12.
So the required equation is
a = 4h.
Answer:
y = 4
Step-by-step explanation:
Step 1: Write equation
9/4y - 12 = 1/4y - 4
Step 2: Solve for <em>y</em>
- Subtract 1/4y on both sides: 8/4y - 12 = -4
- Simplify: 2y - 12 = -4
- Add 12 to both sides: 2y = 8
- Divide both sides by 2: y = 4
Step 3: Check
<em>Plug in x to verify it's a solution.</em>
9/4(4) - 12 = 1/4(4) - 4
9 - 12 = 1 - 4
-3 = -3
Answer:
C. the circumference of a circle
Step-by-step explanation:
The perimeter of a square is the length of the outside, which is found by adding all the side lengths. The circumference of a circle is similar because it is also the length of the outside of the shape.