A patient needs an image produced using a radioactive tracer. A more sensitive detector gives a clear image using a smaller amount of the same tracer. Which change makes best use of the new detector?
Use more tracer to obtain the required image with a lower dose.
Use more tracer to decrease the half-life and improve the image.
Use less tracer to increase the half-life and improve the image.
Use less tracer to obtain the required image with a lower dose.