Please help me with this chemistry question, image attached.

1) This reaction is a double replacement reaction, in which one of the two separate chemicals multiplied with other will switch with the other multiplied chemicals in the products. 2) the expected product for this reaction is Pb(NO3)2 (aq) + 2KI (aq) —> 2K(NO3) (aq) + PbI2 (s), because the chemicals switch with each other to form a solid and another aqueous solution. The equation is then balanced. 3) The term for this solid substance that forms in the reactions product is a “precipitate”.

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later

They are like other investigations? say there was a murder u have to do blood test and finger prints which run through a lab.