Answer: c. sampling error
Step-by-step explanation:
- A population parameter is a number that is evaluated to describe the whole population . For example : Population mean , Population standard deviation etc.
- A sample statistic gives the estimate value of the population parameter. For example : Sample mean , sample proportion.
Since, the sample is a subset of population , so there are chances for unavoidable variation in sample mean from the population mean that varies from sample to sample .
This variation is known as sampling error.
∴ The difference between the value of the sample statistic and the value of the corresponding population parameter is called the sampling error .
Hence,the correct answer is c. sampling error .
Answer:

Step-by-step explanation:
Please consider the complete question.
Sebastian swan laps every day in the community swimming pool. He swam 45 minutes each day, 5 days each week, for 12 weeks. In that time, he swam 1800 laps. What was his average rate in laps per hour?
Let us convert time taken into hours as:


1 hour = 60 minutes. To convert minutes into hours, we will divide total minutes by 60.

Now, we will divide 1800 by 45 to find average rate in laps per hour as:


Therefore, Sebastian's average rate is 40 laps per hour.
Answer:
50% decrease
Step-by-step explanation:
it would be a 50% decrease because half of 8 is 4 and 1/2 is 50 %.
If the two quadrilateral are congruent, then ABCD = PQRS is the correct congruence statement.