1m = 1000 mm
0,4m = 0,4 * 1000 = 400mm
Heat will always flow from High temperature to low temperature
here we know that the temperature inside the room is 60 degree while out side temperature is 80 degree
so the flow of heat is from outside to inside the room as heat flow is always from higher temperature to lower temperature
So after some time due to heat flow from outside the temperature of room will increase
And after long time the temperature of room and outside will be same and heat transfer will become in equilibrium
Answer:
Average speed of car in the first trip is 10 km/hr
Explanation:
It is given that first the car drives 6 hours to the east
Then travels 12 km to west in 3 hours
Average speed for the entire trip = 8 km/hr
Total time = 3+6 = 9 hour
So distance traveled in 9 hour = 9×8 = 72 km
As the car travel 12 km in west so distance traveled in east = 72-12 = 60 km
Time by which car traveled in east = 6 hour
So speed 
So average speed of car in the first trip is 10 km/hr
We can see it as two movements: one on the north-south axis and one on the west-east axis.
On the north-south Axis, the hiker went 8 km north and 4 km south, so in total the hiker went 4 km north (we can subtract one for the other and the direction remains that which was bigger)
On the west-easth Axis, the hiker went 6 km east and 6 km west, so in total the hiker didn't move on this axis! or, he/she moved but then "came back"
So in total, the hiker only moved4 km north - answer B.
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4 m/s because it is THR fastest voice