Let x mph be the speed of the ship in still water.
Against the current, the net speed is, (x-1.9) mph.
Time, t= distance, d/ Speed, v => 9= 113.4/(x-1.9) => 9(x-1.9) = 113.4 => x-1.9 = 113.4/9 => x = 12.6+1.9 = 14.5 mph
Moving with the current, the net speed of the ship = 14.5+1.9 =16.4 mph
Time take, t = d/v = 113.4/16.4 = 6.915 hours
Answer: Convection is the transfer of heat in fluids such as liquids and gases.
Explanation: Any difference in their temperature will cause a transfer of heat. For convection warm fluids rises since it becomes less dense and cooler fluids sinks.
Metals are dense because the molecules are tightly packed together, as opposed to non metal items where molecules are loose and separate. this is why metal is stronger than nonmetal items.
