Answer:
it floats because the lake is cold at that moment so when part of the lake freezes it still remains solid and floats because of the lake and the surrounding of the lake is still cold
According to Ohm's law for a portion of the circuit we have:
U=RI=>I=U/R=24/3=8 A
The correct answer is B
Answer: A.E.
Explanation: To understand the distinction between mass and weight and to be able to calculate the weight of an object from its mass and Newton's law of gravitation. The concepts of mass and weight are often confused. In fact, in everyday conversations, the word "weight" often replaces "mass," as in "My weight is seventy-five kilograms"
Answer:
Too old(Ex. if real time is 1000 then they estimate >1000)
Explanation:
This is because with time our planet may have a definite function which describes temperature.(Because of all the factors and global warming except nuclear bomb testing)
Now nuclear test on planet have significant effect on temperature rise.
Also 14°C rise in temperature is good one because of this.
If future archaeologists only consider that uniform function as above mentioned then they estimate more time then the real one.
Thus too old is right answer.
Answer : The final temperature of the mixture is 
Explanation :
First we have to calculate the mass of water.
Mass = Density × Volume
Density of water = 1.00 g/mL
Mass = 1.00 g/mL × 180 cm³ = 180 g
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.
where,
= specific heat of hot water (liquid) = 
= specific heat of ice (solid)= 
= mass of hot water = 180 g
= mass of ice = 20 g
= final temperature of mixture = ?
= initial temperature of hot water = 
= initial temperature of ice = 
Now put all the given values in the above formula, we get
Therefore, the final temperature of the mixture is
