Each of the following processes involves sampling from a population. Define the population, and state whether it is tangible or conceptual.
a. A shipment of bolts is received from a vendor. To check whether the shipment is acceptable with regard to shear strength, an engineer reaches into the container and selects 10 bolts, one by one, to test.
b. The resistance of a certain resistor is measured five times with the same ohmmeter. A graduate student majoring in environmental science is part of a study team that is assessing the risk posed to human health of a certain contaminant present in the tap water in their town. Part of the assessment process involves estimating the amount of time that people who live in that town are in contact with tap water. The student recruits residents of the town to keep diaries for a month, detailing day by day the amount of time they were in contact with tap water.
d. Eight welds are made with the same process, and the strength of each is measured.
e. A quality engineer needs to estimate the percentage of parts manufactured on a certain day that are defective. At 2:30 in the afternoon he samples the last 100 parts to be manufactured.