Answer:
10
Explanation:
It will be assumed that the disinfection follows the exponential law.
Surviving organisms will remain at the rate of 10% / 10 minutes.
Initial number of organisms = 1000
surviving staphylococcus aureus after 20 minutes
= 1000 * (0.10)^(20/10)
= 1000 * 0.01
= 10
