This is a compound curve here, so it's this section of the right vertical ellipse the orange ellipse this section of the left vertical ellipse, which is the green one and of course, we're going to finish off with the perimeter or the limit of the sphere
這是一條複合曲線,是以它是右側垂直橢圓的這一部分,即橙色橢圓 左側垂直橢圓的這一部分,即綠色橢圓,當然,最後我們還要計算球體的周長或極限。