[填空题]
You have three tuning forks, A, B, and C. Fork B has a frj0k 0 nr-mh5yz44 jmzg3 /kmfvequency hl:8xkcj17 keq/he i(of 441 Hz; when A and B are sounded together, a beat frequency of 3 Hz is heard. When B and C are sounded together, the beat frequency is 4 Hz. What are the possible freque/1lc(8qjexk:k eh7 hi ncies of A and C? What beat frequencies are possible when A and C are sounded together?$f_A$ = Hz or Hz
$f_C$ = Hz or Hz
|$f_A$-$f_C$| Hz or Hz