is saying i've been blocked when all I did was copy and paste this: Which equations support the fact that rational numbers are closed under addition?

Select each correct answer.

13+13=23

6√+(−6√)=0

2√+2√=22√

9√+9√=29√

The stem-and-leaf plot shows the heights in centimeters of teddy bear sunflowers grown in two different types of soil. soil a soil b 5 9 5 2 1 1 6 3 9 5 1 0 7 0 2 3 6 7 8 2 1 8 3 0 9 key: 9|6 means 69 key: 5|8 means 58 calculate the mean of each data set. calculate the mean absolute deviation (mad) of each data set. which set is more variable? how do you know?