Trình bày đặc điểm cấu tạo và chức năng của tủy sống

Plants that have reproductive structures called cones are?

Where are the strongest jet streams located?

If the dimensions of a cube-shaped cell with a length,height, and width of 1 micrometer were to double, what would be the cell's new ratio of surface area to volume? a.3 to 1 b.4 to 3 c.1 to 2 d1 to 6