[填空题]
A science museum has a display ca3t9inwplp 9zbv u+4 -klled a sewer pipe symphony. It consimk)01eosfp p 0sts of many plastic pipes of various le s pe0ok10m)fpngths, 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?
