A and B start from the same point. A cycles 8 km South, then turns to her right and cycles 5 km. B cycles 3 km North, then turns West and cycles 5 km, then turns to her left and cycles 4 km. Where is B with respect to A now?
In a certain code language, '+' represents 'x', '-' represents '+', 'x' represents '÷' and '÷' represents '-'. What is the answer to the following question?
The weights of 4 boxes are 30, 20, 50 and 90 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxes and in a combination a box can be used only once?