Equipment operation & quality control

Which of the following is (are) essential to high-quality mammographic examinations?
1. Small focal spot x-ray tube
2. Short-scale contrast
3. Use of a compression device
High, short-scale contrast (and therefore low kilovoltage) is needed to
accentuate minute differences in tissue density
A compression device serves to
even out differences in tissue thickness (thicker at chest wall, thinner at nipple) and decrease OID, and helps decrease the production of scattered radiation.
Which of the following contribute(s) to base-plus fog?
1. Chemical fog
2. Base tint
3. Background radiation
Base-plus fog should not exceed