An AP axial SI joint x-ray required 30 degrees of tube angulation. How many inches should the tube-to-tabletop distance be adjusted?

From an original technique of 50 mAs @ 75 kVp using a 40-inch SID and a 3-mm focal spot size, which of the following set of technical factors would increase x-ray photon penetration yet maintain overall IR exposure?

In a fixed kVp system, what is varied to maintain a consistent contrast level.

With all other factors unchanged, if SID is increased, exposure to the image recptor will: 

AEC systems require a minimum amount of time for the unit to detect the presence of radiation and respond.

As OID increases, subject contrast

If an object is measured as 4-inches in diameter on the image and is 4-inches from the image receptor, what is the actual size of the object if the SID is 40-inches? Round to the first decimal place and include the correct unit in your answer.

What is the penumbra of an image taken using a 2 mm focal spot, a 42″ SOD, and a 5″ OID?  Answers are rounded to the second decimal place.

Which of the following causes grid cut-off? (select all that apply)

With an SID of 30-inches and an OID of 20-inches, what is the magnification factor?