[填空题]
A helium-filled ball uet7dqat(,h;oon escapes a child’s hand at sea leve*1*cjjxt66+ynwf ,uift v4)gp hg: np x6u2uvl and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level? times the original volume