如图所示，固定的半圆形竖直轨道，AB为水平直径，O为圆心，同时从A点水平抛出甲、乙两个小球，速度分别为v₁，v₂，分别落在C，D两点，OC，OD与竖直方向的夹角均为37°，（sin37°=0.6，cos37°=0.8）则（   ）

    Wugang is the political, education, medical health services and cultural center of southwestern Hunan Province. It has a gross area of 1549 square kilometers, with a population of 832,500. The urban area takes 16.52 square kilometers, with 266,000 urban residents.

    This city has a long history and splendid culture. It was a county built in Western Han Dynasty more than 2200 years ago. It has spectacular landscapes, beautiful and natural scenery. Religions are free and prosperous here. Let me show you a few examples, Yunshan mountain (literal means Cloudland Mountain") is not only famous for its vagaries of clouds, but also known as one of the 72 Buddhist Holly Lands in China, Faxiang Carved Stone (A branch of Buddhism which came from Indian), Sun Yat- sen Memorial Hall, Xuanfeng City Gate Tower, Lingyun Tower (Built in 1225). All of these are showing the rich cultural heritage of this ancient yet vibrant city.

    This land is blessed with unsurpassed natural resources. Coal, Manganese, Iron and other 38 kinds of mineral are proved to be highly productive. Especially, Coal reserves account for 70 percent of proved reserves in Southwest Hunan. What's more, the Marinated Food gains great reputation both at home and abroad. Besides, Virus-free orange and corn are also Wugang's local specialties with high-yield and high-quality.

    Welcome to Wugang.

材料一：某小区退休干部义务担任了“文明使者”、“护绿使者”等职务，暑期他们还组织青少年学生参加社会实践等等，他们用自己的余热为小区三个文明的发展做出了自己贡献。
材料二：某校部分同学参加了“公民教育实践”课题研究，积极研究和解决“城市牛皮癣”问题，他们利用节假日走向社会，清除小广告，为美化城市作出了一名小公民应尽的贡献。
材料三：一位出租车司机向全市的出租车司机发出了“文明在的士，美化新城市”的倡议。结合材料，联系所学知识回答下列问题