题干

如图所示,在大烧杯中,有红、蓝两只彩色气球,红色气球内充有二氧化碳(CO2)气体,蓝色气球内充有空气,两只气球沉在杯底.小明同学收集好一集气瓶CO2气体,倾倒入大烧杯中,发现其中一只气球浮起来了,用手轻轻将其按下,手一松气球又重新上浮,十分有趣。

 

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    Tiny Tomatoes

    Tomatoes come in a variety of sizes, shapes and colors. And the little tomatoes are some of the most fun to grow and are perhaps the most rewarding. 
    Little tomatoes are classified into plum, cherry, grape or currant (醋栗) tomatoes.   ____ Plum tomatoes are the largest of the groups listed, and currant tomatoes are the smallest. There are also differences in color, flavor and skin thickness, but these differences are more relative to specific varieties.____

    Plum, cherry and other small tomato types are fun to grow because they always produce abundant crops of flavorful fruit. They are fun to snack on while working in the garden or while daydreaming about working in the garden.____They are typically sweeter than large tomatoes, and little tomatoes contain less juice and fewer seeds than large tomatoes.

    To grow little tomatoes, select a site that receives at least six to eight hours of full sun per day. Use a large container set in a sunny spot if a sunny planting site is otherwise unavailable.”

    ____You could also plant seeds, but already-started plants will provide fruit much more quickly. Water infrequently to help plants grow deep roots before the heat of summer arrives.

    Harvest fruits when they are ripe. They will generally slip from the plant at this point.____ Store harvested fruit indoors and unrefrigerated as cool temperatures change the flavor.

A. The best time to grow tomato plants is March.

B. Differences in size matter most commonly here.

C. They are also influenced by growing conditions.

D. Then select plants from the garden center or farmers.

E. All of them are delicious and almost of the same size.

F. These are good additions to salads and cooked dishes.

G. But they should feel firm in your hand at the same time.