Answer:
The concentration downstream reduces to 0.03463mg/L
Explanation:
Initially let us calculate the time it is required to fill the lake, since for that period of time the pollutant shall remain in the lake before being flushed out.
Thus the detention period is calculated as

Now the concentration of the pollutant after 14.872 days is calculated as

where
is the initial concentration
't' is the time elapsed after which the remaining concentration is calculated
k is the dissociation constant.
Applying values we get


If one of two interacting charges is doubled, the force between the charges will double.
Explanation:
The force between two charges is given by Coulomb's law

K=constant= 9 x 10⁹ N m²/C²
q1= charge on first particle
q2= charge on second particle
r= distance between the two charges
Now if the first charge is doubled,
we get 
F'= 2 F
Thus the force gets doubled.
Answer: Truck 2, because it has a larger mass than truck 1 (and the same velocity)
Explanation:
We can write the kinetic energy of an object with mass M and velocity V as:
K = (M/2)*V^2
Let's calculate the kinetic energy for each truck:
Now, we can see that both trucks move at the same velocity, but truck 1 has a mass of 5000 pounds, while truck 2 has also a mass of 5000 pounds and an extra of 900 pounds.
Then the total mass of truck 2 is 5000 pounds + 900 pounds = 5900 pounds.
Then both trucks have the same velocity, and truck 2 has a larger mass than truck 1, this implies that truck 2 will have a larger kinetic energy than truck 1.
Static friction because the rocks arent moving are they?