The primary factor that affects radiographic contrast of an image ...

[mcmcdaniel]

The primary factor that affects radiographic contrast of an image is:
 
 time
  mA
  kVp
  mAs

Question 2

Proper tangential imaging of the sesamoid bones in the foot is indicated when:
 
 the sesamoids are projected free of the head of the first metatarsal
  the sesamoids are projected into the base of the first metatarsal
  the sesamoids are projected free of the base of the first metatarsal
  the sesamoids are projected into the head of the first metatarsal

[shaikhs]

Answer to Question 1

kVp

Rationale: Kilovoltage affects contrast on an image, but also contributes to density.

Answer to Question 2

the sesamoids are projected free of the head of the first metatarsal

Rationale: If performed correctly, a tangential, or skimming, beam will cast sesamoids free of superimposition of the head of the first metatarsal.