A radio station has two channels . One is AM at $1020\;KHz$ and the other FM at $89.5\;MHZ$ For good result you will use

Question

$\begin{array}{1 1} \text{longer antenna for the AM channel and shorter for FM channel } \\ \text{Shorter antenna for the AM channel and longer for FM channel } \\ \text{Same length for both } \\ \text{Cannot be determined } \end{array}$