Final answer:
Precision refers to the consistency of measurements, while accuracy relates to the closeness to the true value. Thus, set a is precise but not accurate, set c is both, and set d is neither.
Step-by-step explanation:
When considering the precision and accuracy of a set of measurements, we refer to the consistency and closeness to a target value, respectively. A set of measurements that is precise but not accurate consistently hits the same spot, but not necessarily the intended target. Set c which is both precise and accurate, consistently hits the target spot. Whereas set d is neither precise nor accurate, indicating that the measurements are spread out and do not hit the target consistently.
It’s important to understand that precision refers to the closeness of multiple measurements to each other, while accuracy refers to how close a measurement is to the true value.