Which is likely to produce the shallowest search slopes in a visual search task?

Which is likely to produce the shallowest search slopes in a visual search task?
 
  a. a small range of set sizes
  b. searching for a red X among green Os
  c. a large range of set sizes
  d. searching for a black T among rotated black Ls

Question 2

In visual search, __________.
 
  a. conjunction searches are generally faster than disjunction searches
  b. parallel search generally takes longer than serial search
  c. the kinds of distractors can critically influence search rates
  d. the search slope refers to the cost per additional target in the display

Question 3

If a pop-out effect does not occur, the visual search is best described as a __________ search.
 
  a. failed
  b. obligatory
  c. parceled
  d. conjunction