162. If D is the distance between parallel tracks G is the gauge and a is angle of crossings, the distance between theoretical noses of two crossings measured parallel to tracks, is
A. (D ? G ? G sec a) cot a
B. (D - G + G sec a) cot a
C. (D ? G G sec a) tan a
D. (D + G + G sec a) cot a.

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163. If D is the distance between the parallel sidings and a is the angle of crossing, the distance between the noses of crossing measured parallel to the gathering line, is
A. D tan a
B. D cot a
C. D sin a
D. D cos a.

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164.  If D is the distance between the parallel sidings and a is the angle of crossing, the distance between the noses of crossing measurei3k parallel to the main track, is
A. D tan a
B. D sec a
C. D cosec a
D. D cot a.

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165.  If D is the dis ance between the parallel sidings and 13 is the limiting angle f crossings, the distance between the noses of crossing measu ed parallel to the main track, is
A. D sin 13
B. D cot 13
C. D tan 13
D. D sec 6.

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166. The side of a rail diamond may be obtained by dividing the gauge of track by
A. sine of acute crossing
B. consine of acute crossing
C. tangent of acute crossing
D. cotangent of acute crossi

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167.  If G is gauge distance an4 a is crossing, the distance between the nose of acute crossing nd nose of obtuse crossing of a rail diamond, measured along the rail not forming the diamond, is
A. G cot a
B.G tan a
C. G sin a
D. G cos a.

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168.  A triangle of railway consists of
A. three turn outs
B. one turn out and two diamonds
C. two turn outs and one split
D. one turn out, one split and one diamond.

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