The middle or centre of the Earth is the core. However the middle of the layers from the surface to the centre of the Earth is known as mantle.
Answer:
a)V=18.35 m/s (South -East)
b) t =7.41 m/s
c)D= 66.70 m
Explanation:
Given that
Velocity of boat in east direction = 16 m/s
Velocity of river = 9 m/s
a)The resultant velocity V

V=18.35 m/s (South -East)
b)
We know that
Distance = Velocity x time
Lets t time takes to cross the river
136 = 18.35 x t
t =7.41 m/s
c)
The distance covered downstream
We know that
Distance = Velocity x time
t= 7.41 s
D= 7.41 x 9 m
D= 66.70 m
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.