[填空题]
A tennis ball bounces on the ground,e;ab) m4yjyx n times. The heights of yjfl,.w/+u x uthe bounces, $h_{1}, h_{2}, h_{3}, \ldots, h_{n}$ , form a geometric sequence. The height that the ball bounces the first time, $h_{1}$ , is 80 cm, and the second time, $h_{2}$ , is $60 \mathrm{~cm} $.
1. Find the value of the common ratio for the sequence.
2. Find the height that the ball bounces the tenth time, $h_{10}$ .≈ cm
3. Find the total distance travelled by the ball during the first six bounces (up and down). Give your answer correct to 2 decimal places.≈ cm