Answer:
C, weathering by the water.
Explanation:
While in the river, it scraps againsts other rocks and things, which causes it to change shape. For example be smoother and round.
Answer:
I) 420000J
ii)
Explanation:
(I) so you can use the formula for quantity of heat then substitute the values given
formula-Q=mc∆9
Initial velocity (Vi) = 25 m/s
acceleration (a) = 
time interval (t) = 5 sec
let us assume that final velocity after 5 sec be Vf
As acceleration is constant, we can apply the the equation of motion with constant acceleration i.e. 
Hence, 
so, the velocity of bicyclist will be 5 m/s after 5 sec
The lens equation gives d relation between focal length, object distance n image distance.
1/f = 1/v + 1/u
seldon
<span>2002 seconds, or 33 minutes, 22 seconds.
First, let's calculate how many joules it will take to lift 78 kg against gravity for 1100 meters. So:
78 kg * 9.8 m/s^2 * 1100 m = 840840 kg*m^2/s^2
Now a watt is defined as kg*m^2/s^3, so a division of the required joules should give us a convenient value of seconds. So:
840840 kg*m^2/s^2 / 420 kg*m^2/s^3 = 2002 seconds.
And 2002 seconds is the same as 33 minutes, 22 seconds.</span>