Found a small error... I was in the "Lab0: Using the tools" and I put "500uA" for the answer to "Current flowing into source (amps, with correct sign)". I got

Found a small error... I was in the "Lab0: Using the tools" and I put "500uA" for the answer to "Current flowing into source (amps, with correct sign)". I got an Unknown Error javascript alert. When I removed the "A" from the answer box, all was well.