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In a metal fabrication process, metal rods are produced to a specified target length of 15 feet.  Suppose that the lengths are normally distributed.  A quality control specialist collects a random sample of 16 rods and finds the sample mean length to be 14.8 feet and a standard deviation of 0.65 feet.  The 95% confidence interval for the true mean length of rods produced by this process is ________________________ .

A pharmaceutical company wants to answer the question whether it takes longer than 45 seconds for a drug in pill form to dissolve in the gastric juices of the stomach. A sample was taken from patients taking the given drug in pill form and times for the pills to be dissolved were measured. State assumptions of the test. 

Molly’s Reach, a regional restaurant and gift shop, has recently launched an increased sales campaign, particularly focused on their gift shop. To determine if their proposal is of interest, they plan to survey a random sample of their regular customers. One member of the management team at Molly’s Reach suggests that their survey could be conducted online.  Customers logging on to the online store would be asked to take a few minutes to complete the survey and would be offered a coupon as incentive to participate.  Which of the following statements is true?

Molly’s Reach, a regional restaurant and gift shop, has recently launched an increased sales campaign, particularly focused on their gift shop. To determine if their proposal is of interest, they plan to survey a random sample of their regular customers. All regular Molly’s Reach customers is known as the ________ of the study.

Based on data collected from its production processes, Crosstiles Inc. determines that the breaking strength of its most popular porcelain tile is normally distributed with a mean of 400 pounds per square inch and a standard deviation of 12.5 pounds per square inch.  Based on the 68-95-99.7 Rule, about what percent of its popular porcelain tile will have breaking strengths between 375 and 425 pounds per square inch? 

Shortly after the Sandy Hook Elementary School shooting in December 2012, a local television news program asked viewers to call in with their opinion about gun control.  These results were likely biased because ________________________ .

At a local manufacturing plant, employees must complete new machine set ups within 30 minutes.  New machine set-up times can be described by a normal model with a mean of 22 minutes and a standard deviation of four minutes.  What percent of new machine set ups take more than 30 minutes?

What is the maximum amount that can be invested in an Individual Savings Account (“an ISA”) in 2021/22?

What is the stated purpose of the SRA Financial Services (Conduct of Business) Rules 2001 (“the CoB Rules”)?

Which letter represents the structure that stores tears?