the second is easy there are only three moves white can do against the check :
1. 38.Re3 then Rxe3 wins
2. 38.Ke2 then Re3+ and after king moves Rxe1 and the should be bxf7+ kxf7 and Kxe1 and black has an extra bishop
3.Kf1 then Rh1+ follow by Rxe1+ and Bxe8 and black has two pieces more.
The first is more tricky and i dont see a clear cut move at first glance...
regards
Toni
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