253.  Curves in the same direction separated by short tangents, are called
A. simple circular curves
B. compound curves
C. transition curves
D. broken-back curves.

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254.  The minimum ratio of the radii of two circular curves of a compound curve, is kept
A.1.25
B.1.5
C.1.75
D. 2.0.

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255.  The minimum superelevation in rolling terrain in plains, is limited to
A.4%
B.5%
C.6%
D.7%

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256. If the designed speed on a circular curve of radius 1400 m is 80 km/hour, no superelevation is provided, if the camber, is
A.4%
B.3%
C.2%
D. 1.7%.

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257.  If N is deviation angle, the length L of a parabolic vertical curve for safe stopping distance S, is
A. NS2 if L > S
B. 25 ? ?N tf L < S
C. VS2 if L < S
D. 25 if L > S

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258.  If N is deviation angle the length L of a parabolic vetical curve for overtaking sight distance S, is
A. ?9.6 if L > S
B. 2S ?if L < S
C. 2IS if L < S
D. both (a) and (b).

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259.  The safe length L of a valley curve for night travel is
A.1.50 + 0.035S
B.0 + 0.035S
C. neither (a) nor (b)
D. both (a) and (c).

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