Answer:
The overall reliability is 99.7402 %
Step-by-step explanation:
The overall reliability of the product is calculated as the product of the working probability of the components.
For components A,B,C and F we have :

⇒

For components D,E,G and H we have :

⇒

Finally, for components I and J :

⇒

Now we multiply all the working probabilities. We mustn't forget that we have got ten components in this case :
Components A,B,C and F with a working probability of 0.9999
Components D,E,G and H with a working probability of 0.9997
Components I and J with a working probability of 0.9995
Overall reliability = 
0.997402 = 99.7402 %