The correct answer would be option D.
No, it is not a valid inference because his classmates do not make up a random sample of the students in the school
The population represents all of the students in the school. Apart from his science class there can be students in arts class, music class, literature class and so on. He used convenience sampling by just surveying the students of his science class. The students in science class are those who are interested in science and related topics so these students will be more inclined towards watching a science program. Thus the survey of Johnny does not yield valid result and his inference is not valid.
Thus, option D is the correct answer.
Answer:
θ=0,π/3,π,5π/3,2π
Step-by-step explanation:
cosθ sinθ-1/2 sinθ=0
sinθ(cos θ-1/2)=0
Either sin θ=0
θ=0,π,2π
or
cosθ-1/2=0
cos θ=1/2=cos π/3,cos(2π-π/3)
θ=π/3,5π/3
3) 0.5(12m-22n)=0.5(12m)-0.5(22n)
=6m-11n
4) 2/3(18x+6z) =2/3(18x)-2/3(6z)
=12x-4z
5)2x+12=2(x+6)
6)12x+24=12(x+2)
There isn't any piece of data during Taylor's experiment which can be taken as qualitative. Thus, correct choice is: Option D: None are qualitative.
<h3>What is qualitative data?</h3>
Qualitative data tells about the quality or characteristic. It is tough to express it numerically or not at all expressible numerically. They are usually catagorical.
In contrast, there is quantitative data which can be expressed numerically.
The problem is missing its option, which are:
- mass of the cars
- degree of the ramp incline
- time in seconds
- none are qualitative
Mass can be measured (in kgs, grams etc), degree of inclination can be measured (in radians, degree etc), time can be measured (in seconds, minutes etc).
Thus, there isn't any piece of data during Taylor's experiment which can be taken as qualitative. Thus, correct choice is: Option D: None are qualitative.
Learn more about qualitative and quantitative data here:
brainly.com/question/12929865