如图，圆心都在x轴正半轴上的半圆O₁、半圆O₂、…、半圆O_n与直线y=$\frac{\sqrt{3}}{3}$x相切，设半圆O₁、半圆O₂、…、半圆O_n的半径分别是r₁、r₂、…、r_n，则当r₁=1时，r₂₀₁₆=____ ．

    Liu Tao's grandparents live on the1. They have a big house2 the house, there is a park.

    Today is 3Liu Tao and his parents don't study or 4

Now they are at Liu Tao's grandparents' house. All of them are5 lunch around the table. There are some rice dumplings on the table. Liu Tao likes6 the rice dumplings with meat and eggs. But his parents like the7 with jujube (枣子). Grandpa is telling a 8 about Quyuan.

    They are all listening to him. They are going to watch a dragon boat race in the park in the 9It will be very exciting (令人激动的). Liu Tao likes the races. He can't10 to see.