Answer:
1.778 times more or 16/9 times more
Step-by-step explanation:
Given:
- Mirror 1: D_1 = 8''
- Mirror 2: D_2 = 6"
Find:
Compare the light gathering power of an 8" primary mirror with a 6" primary mirror. The 8" mirror has how much light gathering power?
Solution:
- The light gathering power of a mirror (LGP) is proportional to the Area of the objects:
LGP ∝ A
- Whereas, Area is proportional to the squared of the diameter i.e an area of a circle:
A ∝ D^2
- Hence, LGP ∝ D^2
- Now compare the two diameters given:
LGP_1 ∝ (D_1)^2
LGP ∝ (D_2)^2
- Take a ratio of both:
LGP_1/LGP_2 ∝ (D_1)^2 / (D_2)^2
- Plug in the values:
LGP_1/LGP_2 ∝ (8)^2 / (6)^2
- Compute: LGP_1/LGP_2 ∝ 16/9 ≅ 1.778 times more
The best answer out of the ones provided would be c, confidence interval
Statistic significance requires that your sample be representative of the population, but I'm struggling with this because if the class is an elective then the answer would be: <span>No, it is not a valid inference because she asked all 22 students in her science class instead of taking a sample of the students in her school.
BUT if the class is required, as most science classes are, then it WOULD be a random sample of the school. So the last option would be correct.
My guess though is that the teacher is looking for answer B.
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