1) 100 * 40 = 4000 (cm²) the area of rectangle
2) 40 * 30 * 1/2 = 600 (cm²) the area of triangle
3) 4000 + 600 = 4600 (cm²)
Answer: 4600 cm²
-4x^4 - 15x^2 + 1 - 19/x^2 is your answer
Hope I helped :)
C.
24 means that you earned 6 dollars an hour for 4 hours. 2.5n means that for every person, n, you receive an additional $2.50.
A) 0.9803; 0.4803
B) 32
We calculate the z-score for this problem by using the formula:

Using our formula, we have:

Using a z-table (http://www.z-table.com) we see that the area to the left of, less than, this score is 0.9803.
To find the probability it is between the mean and this, we subtract the probability associated with the mean (0.5) from this:
0.9803 - 0.5 = 0.4803.
To find B, we first find the z-score for this. Using a z-table (http://www.z-table.com) we see that the closest z-score would be 2.33. We then set up our equation as

Multiplying both sides by 0.85 we have
2.33(0.85) = 0.35√n
1.9805 = 0.35√n
Divide both sides by 0.35:
1.9805/0.35 = √n
Square both sides:
(1.9805/0.35)² = n
32 ≈ n
165÷11=15
120÷15=8
so the answer should be 8