In task one the extract was talking about someone who sounds like a professional hitman/assassin because it talks about a man with a knife in his hand . The text also said that the knife was sharper than any razor and if it sliced you,  you wont know whats happening. It makes it seem like an assassin was the peraon who did it because it said that it was brought to do what it was ment to and knifes are normally for making food or inflicting wounds on someone by stabbing them. Also the house may have been brokwn into due to the text saying the street door was still open and he used that door to slip into the house unnoticed. He seem to have to kill the family inside because it says one more left.