At start ( t = 0 nanoseconds ) :
E ( t = 0 ) = 2.645 J
E ( t = 1 ) = 6.290 J
E ( t = 1 ) : E ( t = 0 ) = 6.290 : 2.645 = 2.37
Also:
E ( t = 2 ) : E ( t = 1 ) = 14.909 : 6.290 = 2.37
E ( t = 3 ) ; E ( t = 2 ) = 35.335 : 14.909 = 2.37
Therefore, the formula for calculating the energy of the system is:
E ( t ) = 2.645 * 2.37 ^ t
The answer is 4) exponential growth.