How come there is only 3 c5h12 isomers?

That's because the first and last carbon atoms cannot be branched to form an isomer . Therefore only the three middle carbon atoms can form isomers.

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.

the answer is true. hope it .