Which of the following is one of the commercial products obtained from Gelidium and Gracilaria and are used to grow microbes and in preparations of ice- creams and jellies?
P and Q start cycling from the same point. P cycles 18 km North, then turns to her right and cycles 3 km. Q cycles 9 km East, then turns North and cycles 10 km North, then turns left and cycles 6 km. Where is Q now with respect to the position of P?
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 20, 40, 80 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?