Answer: The answer is 314.28 cm² (approx.).
Step-by-step explanation: Given that an engineer is going to install a new water pipe. The diameter of this circular pipe is, d = 20 cm.
We need to find the area 'A' of the circular cross-section of the pipe.
Given, diameter of the circular section is

So, the radius of the circular cross-section will be

Therefore, cross-sectional area of the pipe is

Thus, the answer is 314.28 cm² (approx.).
X > 6 i think is the answer
Answer:
Step-by-step explanation:
First and foremost, all quadratics have a domain of all real numbers (as long as we are not given only a portion of the graph, or one with endpoints. Our graph does not have endpoints, so it is assumed that the tails will continue to go down into negative infinity and at the same time, the x coordinates will keep growing as well.) Since our quadratic is upside down, it has a max. That means that none of the values on the graph will be above that point. All the values will be below that highest point (the highest y-value). Y-values indicate range, and since our highest y-value is at y = 2, then the range is
y ≤ 2
Answer: 2,215,000
Step-by-step explanation:
Given: The quadratic function
models the population of a city where x represents the number of years since 2005.
To Find: population of the city in 2010
We need to put x= 2010-2005 = 5

Hence, the estimated population of the city in 201 = 2215 thousands or 2,215,000 .