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, dinoflagella A. sand color B. red pigments in coastal waters C. blue pigment D. reflected light and yellow pigment from plant life [简答题]简述MPLS标签栈的概念
[填空题]闭塞设备分为自动闭塞、 ___闭塞和半自动闭塞。
[单项选择]依据《安全生产法》的规定,给予生产经营单位予以关闭的行政处罚由( )按照国务院规定的权限决定。
A. 负责安全生产监督管理的部门 B. 负责安全生产监督管理的部门会同工商、税务部门 C. 负责安全生产监督管理的部门报请县级以上人民政府 D. 负责安全生产监督管理的部门会同相关行业主管部门 [单项选择]在百科全书网http://countries-book.db66.com上进行书目查询,实际上查询的是()。
A. 电子表格 B. 图片文件 C. 数据库 D. 文本文件 [不定项选择题]车站通风系统由隧道通风系统、车站公共区通风系统(大系统)、车站管理用房通风系统(小系统)组成。
A.隧道通风 B.车站公共区 C.车站管理用房 D.站厅区 E.站台区 [单项选择]色彩深度是指在一个图像中什么的数量()
A. 颜色 B. 饱和度 C. 亮度 D. 灰度 [简答题]
2011年6月8-9日,中国海军共11艘护卫舰从东海经冲绳本岛与宫古岛间的公海水道驶向太平洋。中国国防部明确表示,这是中国海军的年度计划内例行性训练,符合相关国际法准则,不针对任何特定国家和目标。 [单项选择]患者男,45岁,因“项部发际处皮疹伴痒3年”来诊。查体:项部发际处有一4cm×4cm的粉红色肥厚性斑块,上覆细鳞屑,边缘浸润;双肘部肥厚性斑片。不适宜的治疗方法是()
A. 外用糖皮质激素类软膏 B. 采用封包疗法 C. 外用炉甘石洗剂 D. 洗浴后外用护肤品 E. 尽量避免搔抓 我来回答: 提交
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