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A seed appears on an image measuring 11mm.  The actual seed is 8mm.  What is the magnification factor if the source to image receptor distance is 115 cm?

A partial arc treatment will rotate 220 degrees for the daily treatment of 180 cGy.  The MU setting is 191.  Calculate the gantry speed.

The patient’s original treatment plan was to midplane for an AP/PA spine treatment.  However, the radiation oncologist decided to make a 3 cm posterior isocenter shift.  What is the new SSD if the patient’s separation is 24 cm?

When MLC blocking is used in a treatment calculation, the area of the collimator is used in determining: I.   TMR II.  Sc III. PDD

Calculate the therapeutic ratio given a lethal dose of 4000 cGy and normal tissue tolerance of 6500 cGy.

Regarding the multiple beam alignment check, which of the following are general causes of beam misalignment? I.      Focal spot displacement II.     asymmetry of collimator jaws III.    Displacement in the collimotor rotation axis or the gantry rotation axis  

In particle therapy, which of the following factors can impact the range uncertainty? I.    Dose calculations II.   Setup III.  Organ and Anatomic Variations IV.  X-ray Energies

The coulomb is the metric unit of electrical ______________.

Which hinge angle below requires a 60-degree wedge to reduce the hot spot?

A port film is taken at 130 cm from the source.  The irradiated field measures 16 x 16 cm on the imager.  What does this field size measure at the isocenter?