Answer:
a
Step-by-step explanation:
<span>Let the number be x.
The quotient of negative 1 and the product of a number and 21 is -1/21x</span>
According to the rules of indices:
1/a^b=a^-b
thus using this rule, our value will be expressed as follows:
1/z^9=z^-9
Hence the answer is: z^-9
Collecting data through observation involves looking directly at an on going behavior about a phenomenon in its natural setting. Here you observed statistical data present in the web about the school's performance on SAT subject.
Step-by-step explanation:
Demographics are statistical data about a trend in a population such as scores, gender or income. In Observation method you simply check and see what has been happening in a population using available data concerning a phenomenon. Here , searching in the web for data about score on SAT subjects for the school will give you the idea of previous performance by students in that school which could help you come up with a hypothesis structured around these results.
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- Data collection methods https://brainly.in/question/1305596
Keywords : Data collection methods, demographics, case study
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