The complete queston is The amount of a radioactive element A at time t is given by the formula
A(t) = A₀e^kt
Answer:  A(t) =N e^( -1.2 X 10^-4t)
Explanation:
Given 
 Half life =  5730 years. 
A(t) =A₀e ^kt
 such that
A₀/ 2 =A₀e ^kt
 Dividing both sides by A₀
 1/2 = e ^kt
 1/2 = e ^k(5730)
 1/2 = e^5730K
 In 1/2 =  5730K
k = 1n1/2 / 5730
k = 1n0.5 / 5730
K= -0.00012 = 1.2 X 10^-4
 So that expressing   N in terms of t, we have 
A(t) =A₀e ^kt
 A₀ = N
A(t) =N e^ -1.2 X 10^-4t
 
        
             
        
        
        
Current.A moving charge is an object that changes position to one particular obsever. 
        
             
        
        
        
<span>Assuming that the momenta of the two pieces are equal: when they have equal velocities, then
the masses of the two pieces are also equal.
Since there is no force from outside of the system, the center of mass moves on with the same velocity as before the equation. So the two pieces must fly at the side side of the mass center, i.e., they must always be at 90° to the side of the mass center. Otherwise it would not be the mass center, respectively the pieces would not have equal velocities.
This is only possible, when the angle of their velocity with the initial direction is 60°.
Because, cos (60°) = 1/2 = v/(2v).</span>
        
             
        
        
        
Answer:
The equilibrium position will shift towards the left hand side or reactants side
Explanation:
Decreasing the volume (increasing the pressure) of the system will shift the equilibrium position towards the lefthand side or reactants side. This is because, decreasing the volume (increasing the pressure) implies shifting the equilibrium position towards the side having the least number of moles.
There are two moles of reactants and a total of three moles of products(total). Hence decreasing the volume and increasing the pressure of the gas phase reaction will shift the equilibrium position towards the lefthand side.
 
        
             
        
        
        
Answer:
The air is contained at a high pressure in the tube. When it escapes from a small orifice, it suddenly expands. A large amount of its heat is absorbed in the process of expansion resulting in considerable fall in its temperature. This is why the escaping air feels cold.