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Question 1

Types of horizontal angles

Answer 1

Interior and exterior angles

Angles to the right

Deflection angles, observed from an extension of the back line to the forward station always <180. Can be observed clockwise or counterclockwise

Question 2

Types of reference line

Answer 2

Meridian, chosen reference line for horizontal angles:

1. Geodetic meridian, north south line passes through a MEAN of the earth
2. Astronomic meridian, north south line passes through INSTANTANEOUS of the earth
3. Magnetic meridian, by a compass. Have magnetic declination (horizontal angle from geodetic meridian to the magnetic meridian). It undergoes continual change because magnetic pole are constantly changing.
4. Grid meridian, geodetic north which is parallel in entire area
5. Record meridian, taken from the previous survey
6. Assumed meridian, by assigning any arbitrary direction

Question 3

Difference between azimuth and bearing

Answer 3

Azimuth:

• from 0-360
• only number
• maybe geodetic, astronomic, grid, magnetic, assumed, forward or back
• clockwise
• measured from north

Bearing

• from 0-90
• alphabet and number
• same as azimuths
• clockwise and counterclockwise
• measured from north and south