1. is MgB2 brittle? can we draw it like wire and wind it up make a coil/electromagnet with it? 2. liquid nitrogen boils at 77K and freezes at 63K. most superconductor experiments use liquid nitrogen, so does it mean most applications use this temperature range (eg. for squid)? what about those people using liquid nitrogen for mgb2 experiment? use liquid helium? thanks.