题干

2005年7月18日《齐鲁晚报》报道:欧洲极品海水鱼类——地中海鳎鱼,在山东省威海市人工育苗成功。该鱼种个大肉厚,体形修长、优美,肉质具有特殊的甜味,适合在我国南北方大面积推广养殖。在威海市水产研究所有8个池塘,其中6个池塘养的是鲫鱼,另外两个池塘养的是地中海鳎鱼。那么,这8个池塘里的鱼可看做   (   )

A:一个群落

B:一个生态系统

C:八个物种

D:八个种群

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D

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    The value-packed, all-inclusive sight-seeing package that combines the best of Sydney's harbor, city, bay and beach highlights.

    A SydneyPass gives you unlimited and flexible travel on the Explorer Buses: the ‘red' Sydney Explorer shows you around our exciting city sights while the ‘blue' Bondi Explorer visits Sydney Harbour bays and famous beaches. Take to the water on one of three magnificent daily harbor cruises (游船). You can also travel free on regular Sydney Buses, Sydney Ferries or CityRail services (limited area), so you can go to every corner of this beautiful city.

    Imagine browsing at Darling Harbour, tasting the famous seafood at Watsons Bay or enjoying the city lights on an evening ferry cruise. The possibilities and plans are endless with a SydneyPass. Wherever you decide to go, remember that bookings are not required on any of our services so tickets are treated on a first in, first seated basis.

    SydneyPasses are available for 3, 5 or 7 days for use over a 7-calendar-day period. With a 3 or 5-day pass you choose on which days out of the 7 you want to use it. All SydneyPasses include a free Airport Express inward trip before starting your 3, 5 or 7 days, and the return trip is valid  for 2 months from the first day your ticket was used.

    SydneyPass Fares


Adult

Child*

Family**

3-day ticket

$90

$45

$225

5-day ticket

$120

$60

$300

7-day ticket

$140

$70

$350

*A child is defined as anyone from the ages of 4 years to under 16 years. Children under 4 years travel free.

**A family is defined as 2 adults and any number of children from 4 to under 16 years of age from the same family.