What is your speed
<br /="/"/><div>when you run on an escalator relative to the distance in the building (3 dimensions)? Is it equal to your speed relative to the escalator plus the escalator speed or less than that? Ignore the air.</div><span style="display:none;">www.ddhw.com</span><br /="/"/><br /="/"/> <div style="MARGIN-TOP:20px;MARGIN-LEFT:0;MARGIN-BOTTOM:0;float:left"></div>回复：What is your speed
<table cellpadding="8" height="100%" width="100%"><tr><td valign="top"><br /="/"/><div>why not?</div><span style="display:none;">www.ddhw.com</span><br /="/"/><br /="/"/> <div style="MARGIN-TOP:20px;MARGIN-LEFT:0;MARGIN-BOTTOM:0;float:left"></div></td></tr></table>
页:
[1]