retarded or not?

are you handi-tarded , or careless?

1 64 - 15 subtract
2 678 + 22 adding
3 14 x 2 timesing
4 84 + 84 adding
5 if you have a bucket with 5 gallons in it, and another with 3.5 gallons in it. hows many buckets do you have??
6 how much wook could a wood chuck chuck if a wood chuck could chuck wood??
7 if your uncles step brother has a child, what does that make you??
8 if a penguin weighed 22.5 kg's, and a giraffe weighed 480 kg's, how much would a hippo weigh?