Multiple "IF" formula with "OR" conditions (or a better way?)

Hi

I am trying to workout bonus entitlements for various departments based on performance ratings where some departments will get a different entitlement on their score.

I attach an example of what I am trying to do i.e. All departments get a bonus for 4 and 5 ratings but the Defence projects get an additional "extra bonus" for a 5. Only North and South get it for a 3 and nothing for all for 2 and below.

Thank you

Regards

Cortlyn