问题
选择题
春秋时期，诸侯争霸战争的客观进步作用有
①在一定程度上削弱了奴隶主贵族集团的势力②促进华夏族与其他各族的融合③加快了统一的趋势④便利了新兴地主势力的发展 [ ]
A．①②③
B．②⑧④
C．①③④
D．①②③④
答案
答案：D
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春秋时期，诸侯争霸战争的客观进步作用有
①在一定程度上削弱了奴隶主贵族集团的势力②促进华夏族与其他各族的融合③加快了统一的趋势④便利了新兴地主势力的发展 [ ]
A．①②③
B．②⑧④
C．①③④
D．①②③④
答案：D
| The blue of the sea is caused by the scattering of sunlight by tiny particles suspended in the water. Blue light, being of short wavelength, is scattered more efficiently than light of longer wavelengths. Although waters of the open ocean are commonly some shade of blue, green water is commonly seen near coasts, especially in tropical or subtropical regions. This is caused by yellow pigments being mixed with blue water. Phytoplankton are one source of the yellow pigment. Other microscopic plants may color the water brown or brownish-red. Near the shore, silt or sediment in suspension can give water a brownish hue. Outflow of large rivers can often be observed many miles offshore by the coloration of suspended soil particles. Marine phytoplankton (Greek for "plant wanderers") are microscopic single-celled plants that include diatoms, dinoflagellates, coccolithophorids, green algae, and blue-green algae, among others. The growth of these organisms, which photosynthesize light, depends on a delicate balance of nutrient enrichment via vertical mixing, which is often limited by the availability of nitrogen and light. Diatoms are one-celled plants with patterned glass coverings. Each glass, or silicon dioxide box, is ornamented with species-specific designs, pits, and perforations making them popular with microscopists and, more recently, electron scanning microscopists. |
Which of the following is NOT a type of phytoplankton
A．Green algae.
B．Diatoms.
C．Blue-green algae.
D．Amoeba.