Answer:
1) 8
2) 3
3) 4
4) 5
5) 6
6) 2
7) 1
8) 18
Explanation:
whenever you see a letter, just change that letter with whatever the guide says, for example, 6+c would be 6+2, which is 8. Another example is ab, which would be 6 times 3 because a is 6 and b is three