It’s either snow or rain if it’s a riddle sort of.
Answer:
Lifting force, F = 21240 N
Explanation:
It is given that,
Mass of the helicopter, m = 1800 kg
It rises with an upward acceleration of 2 m/s². We need to find the lifting force supplied by its rotating blades. It is given by :
F = mg + ma
Where
mg is its weight
and "ma" is an additional acceleration when it is moving upwards.
So, 
F = 21240 N
So, the lifting force supplied by its rotating blades is 21240 N. Hence, this is the required solution.
Answer:
A) Cold object will start getting hot
B) Heat exchange will stop as the two object acquire the same temperature.
Explanation:
A) When one hot object and one cold object are kept in contact then the heat is transferred from the hot object to the cold object via different modes of heat transmission. Hence, the cold object starts getting hot
B) The transmission of heat from the hot object to the cold object will stop as the temperature of the two object becomes equal to each other.
The french revolution led to many deaths and impacted history because of the amount of life lost