-- card: 42016 from stack: in
-- bmap block id: 0
-- flags: 0000
-- background id: 2707
-- name: #153
----- HyperTalk script -----
on openCard
  global group,rightone
  put 13 into group
  put "D" into rightone
  pass openCard
end openCard



-- part contents for background part 20
----- text -----
Question #153

-- part contents for background part 1
----- text -----
N3A05  When a signal travels along the surface of the Earth, what is this called?

-- part contents for background part 11
----- text -----
Sky-wave propagation.

-- part contents for background part 27
----- text -----
Knife-edge diffraction.

-- part contents for background part 28
----- text -----
E-region propagation.

-- part contents for background part 29
----- text -----
Ground-wave propagation.

-- part contents for background part 43
----- text -----
Correct answer is D

-- part contents for background part 45
----- text -----
ARRL Handbook Chapter 22