What mistake did Pasteur's assistant make? He didn't refrigerate his cultures.
He waited longer than usual to check for results.
He injected too much of the culture.
He used an old culture of germs.

He used an old culture of germs.

Explanation:

The chickens did not become ill. Pasteur reasoned the factor that made the bacteria less deadly was exposure to oxygen.

He waited longer than usual to check for results.

Explanation:

In 1879, Pasteur observed, by chance, that old bacterial cultures lost their virulence. He had instructed an assistant to inject the chickens with a fresh culture of the viral bacteria before a holiday. The assistant, however, forgot and went on vacation.

Certified answer

35 is your answer because i looked it up