[填空题]
A heater coil connectedl.) )l (x dnywu()ghi*q4n j b,klhz*x to a 5h afjtgg ;6o;j64bhhh 3su +oipg-o7$240-V_{rms}$ ac line has a resistance of $34\Omega$.
(a) What is the average power used? W
(b) What are the maximum and minimum values of the instantaneous power?
$P_{max}$ W
$P_{min}$ W
