Answer:
The service level for each component must be 97.91%
Step-by-step explanation:
If we want a 90% confidence of starting on time, that means we need

As the probability of each component being ready is independent from the others, that means that the probability of the 5 components being ready is equal to multiply each probability:

The probability of being ready on time is equal to the service level (in fraction), and all 5 are equal so we can say:
![0.9=(\mbox{service level(in fraction)})^5\\\\\sqrt[5]{0.9} =\mbox{service level(in fraction)}=0.9791\\\mbox{In percentage}: \mbox{service level (in fraction)}*100 = 97.91\%](https://img.qammunity.org/2020/formulas/engineering/college/3gb3xyjwqoai37aki939u7l7cxvgwhvf81.png)