reporter: that s when the fourth grade teacher received calls at her school threatening wage garnishment. you are responsible for this portion of the bill. reporter: it turns out technically that message from the debt collector is correct. by simply signing a refusal of service form like this one releasing the ambulance of liability, you can be held liable for the bill and in fact you might be even if you don t sign it. true. they can send a bill. reporter: overseeing emergency services for the city and county of san francisco. they provided a response. they arrived so it is usually in their best interests to attempt to recoup the costs. reporter: but how much you get build depends on who responds. we compiled this consumer watch database which shows minimum fees range from $140 to $5000 and some of the highest fees are in cities like san francisco that have an open 911 system. san francisco fire department communications center. reporter: meaning the fire d
debut since google went public 7 years ago. shares started at $45 and tripled by noon, finally closing at $94. tonight in sill silicon valleys david louie reports, they are asking who is next. reporter: at linkedin head quarters, employees celebrated with smoothies and krispy kreme donuts. overnight, this company was worth $8 million, turning some of the private investors into multimillionaires. a great time to be looking for money. not only institutional money, it is the public. and when those two entities are aligned good things happen. reporter: linkedin is the first of the privately held social network companies to go private. waiting in the wings are facebook and twitter. neither has indicated when it will be their turn but linkedin has indicated their time could be near. these are valuable companies, making cash, you know, they have strong business models. we are at a stage now, social media is maturing, i guess. reporter: it gives hope to the plethora of star