text: physics question.can u help plz?? hello, how r u guys?? oh plz i need help in a physics question i really tried alot and alot to do it but it didn't work with me. here is the question: the mass of a full bottle of cooking oil is 1.3 kg. when excatly half of the oil has been used, the mass of the bottle plus the remaining oil is 0.9 kg. what is the mass of the bottle? plz show ur work .. i really need help:( thanx ok .. we have 1.3 total  this includes the bottle , now we have 0.9 left and we know what has disapeared is 0.4 this is only oil so the total of oil would be 0.8  now we know what is left is the bottles weight  0.5  ........