Answer
$\approx 585.35$kg
Work Step by Step
Given: $A_0=1000$ and $A= 800$
Now, we have $A=A_0e^{k t}$
Then $k=\dfrac{\ln (0.8)}{10} \implies A=(1000) e^{\frac{\ln (0.8)t}{10}}$
Now, when after another t = 14 hours, that is, $t=14+10 =24$
$A= (1000) e^{\frac{\ln (0.8)}{10}(24)}$
Hence, $A \approx 585.35$kg
