prepaid phone cards

Hi..

I have a quistion about prepaid phone cards. I can buy prepaid simcards with 140$ funds on it for 42$!

Is there a way to earn money on this kinds of prepaid phone cards?

About content sms.. There is a limit of 2$ pr sms and max 3,50$ per day.

MMS to foreign number cost 0,50$

Is there any method to empty these cards to my benefit ?

Thanks

You can buy bitcoin with sms in order to empty the sim cards, but it depends if this service is avaiable in your country.

I'm also interested to know

I dont know how bitcoins work.

1 bitcoin = +200$ thats huge. Then I cant see how bitcoin could work to empty the cards ??