I do believe it is 12 as well considering the fact that it's negative three and not positive. If it was a positive three then maybe it would be 18.
The answer would be 26 because you're multiplying .5 times 52
It would equal 15. To get 15, you would first do 1*10= which equals 10. After that, you would add 5 to the 10 then there's your answer. I hoped this helped!