1)A plane was detected at 6000m right above observation post A.20 seconds later,the plane was detected at 5000m right above observation post C.Given that the two observation posts were 2400m apart,what was the speed of the plane in km per hour?(Suppose the plane was travelling in a straight line.)
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2)The figure shows a swimming pool of length 50m,width 20m and depths 1.5m and 5m at the two wnds.
Given that the area of a tile is 0.25m^2,how many tiles are needed to cover the bottom of the swimming pool?(Given the answer correct to the nearest integer.)
