Answer:
$0.54
Explanation:
Cost of each song is $1.39
He has a gift card of $20 from which he can buy songs .
So, number of songs he can buy from the gift card =

= 14.388
So, he can buy 14 songs from the gift card
Cost of 1 song = $1.39
So, cost of 14 songs =

=

So, he can spend $19.46 to buy as many songs without going over the gift card limit
So, balance on gift card =

=

Hence ,The balance on the gift card if you download as many songs as without going over the gift card limit is $0.54