In the Previous Problem, the Amount of Chemical $C , X ( t )$

In the previous problem, the amount of chemical $C , X ( t )$ , produced by time t is

A) $x = 2000 \left( 1 - e ^ { - 25 k t / 3 } \right) / \left( 16 - 15 e ^ { - 25 k t / 3 } \right) , \text { where } k = 3 \ln ( 5 / 4 ) / 250$
B) $x = 2000 \left( 1 - e ^ { - 125 k t } \right) / \left( 4 - e ^ { - 125 k t } \right) , \text { where } k = \ln ( 19 / 16 ) / 1250$
C) $x = 400 \left( 1 - e ^ { - 25 k t / 3 } \right) / \left( 3 - e ^ { - 25 k t / 3 } \right) , \text { where } k = 3 \ln ( 3 ) / 250$
D) $x = 400 \left( 1 - e ^ { - 125 k t } \right) / \left( 3 - e ^ { - 125 k t } \right) , \text { where } k = \ln ( 3 ) / 1250$
E) $x = 800 \left( 1 - e ^ { - 25 k t / 3 } \right) / \left( 4 - e ^ { - 25 k t / 3 } \right) , \text { where } k = 3 \ln ( 7 / 4 ) / 250$