[填空题]
A helicopter is ascev1ft4e3 uy: nb 8k,pnlnooe, fn djr a .p 3f:2ocf6.zsm,i5di4ding vertically with a speed of $9.50 \; m/s$. At a height of 225 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground? $s$ [Hint: The package’s initial speed equals the helicopter’s.]
