So this is a hard prediction what the period of an oscillation - should be — 21.5 plus or minus a half second.

因此这是个艰难预测，震荡的周期，应该是-，21。5加减0。5秒。

youdao

So this is a hard prediction what the period of an oscillation - should be — 21.5 plus or minus a half second.

因此这是个艰难预测，震荡的周期，应该是-，21。5加减0。5秒。

youdao