[填空题]
A science museum has a display called a dn rwr:6 zfd-)sewergduumo2f8 f.ixe x (1+kwa2m2 pipe symphony. It consists of many plastic pipes of v 2fumwxk(+mf2 .gi18eox2 ud aarious lengths, which are open on both ends.
(a) If the pipes have lengths of 3.0 m, 2.5 m, 2.0 m, 1.5 m and 1.0 m, what frequencies will be heard by a visitor’s ear placed near the ends of the pipes?
$f_{3.0}$ = Hz
$f_{2.5}$ = Hz
$f_{2.0}$ = Hz
$f_{1.5}$ $\approx$ Hz (Round to the nearest integer)
$f_{1.0}$ $\approx$ Hz (Round to the nearest integer)
(b) Why does this display work better on a noisy day than on a quiet day?
