Conditional probability

[slow salmon]

How do I solve this problem? How do I complete the 2x2 table? Problem: In the production of waterproof smartphone cases, quality control classifies 90% of the cases as waterproof. In reality, 87% of all cases are waterproof, and 8% of all cases are not waterproof and are also identified as not waterproof by the control.
Determine the probability that a case
a) is not waterproof, given that the control classifies it as not waterproof.
b) is waterproof, given that the control classifies it as waterproof.

[craggy spade]

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[slow salmon]

I defined w=the case is waterproof, not w= it’s not waterpoof, k=the control says it‘s waterproof, not k= the control says it‘s not waterproof. Here is my 2x2 table:

is it so far correct? my teacher says it‘s not correct