at his eye would the diameter of her apparent disc subtend?

Ans. Twice the angle whose natural cosecant is thrice radius, that is, twice 19° 28′ 16′′ or 38° 56′ 32′′.

80. In a plane triangle ABC are given

cot A cot B = ,cot в cot c =

to find the angles A, B, and 6.

Ans. 45°, 63° 26' 6", and 71° 33' 54".

1

81. In a certain north latitude it was observed that on the morning of the longest day the body of the sun occupied precisely 8 minutes of time in rising out of the horizon. What the latitude?

Ans. 61° 29' 54" disregarding refraction and parallax: or, 62° 28′ 54′′, taking the horizontal refraction at 33', and the parallax at 9".

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