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A radiation therapist is standing 28 cm from a radioactive source, which is resulting in an exposure rate of 9 mR/hour. In order to reduce the exposure rate to 0.06 mR/hour, at what distance must the therapist be standing?

Calculate the minimum skin gap between field A which has a SSD of 105 cm with a field size of 6 x 12 cm and field B with a field size of 7 x 14 cm and an SSD of 110 cm. The depth of match is 8 cm. What is the skin gap?

During CT simulation of the thorax, a lesion in the cervix is at a distance of 40 cm from the image detectors and an object to image distance of 4 cm. The lesion measures 3.7 cm on the image. Determine the object size of the lesion?

The function of the flattening filter is to

Which of the following is not a common consideration in obtaining computed tomography scans for treatment planning?

Which of the following xray beams will account for the most lateral bulging outside the planned treatment filed?

When the end of the electron cone cannot be directed parallel to a sloping surface, which angle of obliquity will cause the greatest increase in altered dose distribution?

Dose that is received within bone is mainly dependent on 

The wedge angle is determined by the isodose lines at 

A patient is being treated on a 6 MV linear accelerator at 100 SSD with a reference dose rate of 0.998 cGy/MU. The collimator setting is 13 x 13 with a scatter factor of 1.007. The blocked field has an equivalent factor square of 7 x 7 with a phantom scatter of 0.997. The dose to be delivered is to a depth of 8 cm with a percentage depth dose of 79.3. The prescribed dose is 350 cGy per fraction. The doctor orders a parallel opposed AP/PA. What is the MU for each portal?