In spherical coordinates, unit vectors are functions of which of the following coordinate variables（）
A. Spherical radial （R）
B. Spherical longitudinal coordinate （φ）
C. Spherical latitudinal coordinate （θ）
D. All
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In cylindrical coordinates, the radial and angular unit vectors are dependent on which of the following coordinate variable（）
A. Radial coordinate （r）
B. Angular coordinate （θ）
C. Vertical coordinate （z）
D. None
下列种名书写正确的是（）
A. Lycium barbarum L
B. Panax ginseng C. A. Meyer
Cordyceps Sinensis （Berkeley） Saccardo
Dimocarpus longan Lour
E. Hippophae rhamnoides L. subsp. sinensis Rousi
F. Hippophae rhamnoides L. subsp. sinensis Rousi
Which of the following is called the “national epic of the Anglo-Saxons”（）
A. Beowulf
B. The Canterbury Tales
C. Anglo-Saxon Chronicle
D. Morte d’Arthur
Which work inspired Milton to compose his poem, Paradise Lost（）
A. The Old Testament
B. Illiad
C. The Canterbury Tales
D. King Arthur
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