Weibull distribution

OK, one more question. This is for my husband who is studying for the ASQ CQE. There are a few questions on the sample test that he cannot figure out how to solve.

A series system contains three subsystems with the following distributions. If the system is operated for 5,000 hours, what is its reliability?

He can figure out Subsystem 1 & 3. He doesn't know how to figure out the Weibull distribution with the information given.

Here is the question. It is question 65, page 14: https://asq.org/cert/resource/pdf/sample-exam/cqe-sample-exam.pdf

Thank you!