Task: Question Answering
Input (English): Examine each of these chemical equations to determine which equation is correctly balanced.  
 (A) Mg(NO_{3})_{2} + K_{2}CO_{3} -> MgCO_{3} + KNO_{3} (B) Mg(NO_{3})_{2} + K_{2}CO_{3} -> MgCO_{3} + 2KNO_{3} (C) 2Mg(NO_{3})_{2} + K_{2}CO_{3} -> 2MgCO_{3} + KNO_{3} (D) Mg(NO_{3})_{2} + 2K_{2}CO_{3} -> MgCO_{3} + 2KNO_{3}
Output (English): B