Write the name of this property 42+0 = 42

This is the Identity property of addition.  anything+0=that same number
Since adding 0 to a number still makes it the same number, its "identity" is still the same, thus the name.

That is the identiy Property of additon 

anthing times 0 is the same number 

hope this helps :) 

The ratio is 2 weeks:6 centimeters, so let’s simplify: To know how much it grew in ONE week, we need to divide by 2, so 2/2=1 and 6/2=3 so the ratio now is 1:3 now, we multiply those by the number of weeks: 6. So 1x6=6 and 3x6=18 the ratio is 6:18. The plant will be 18 centimeters after 6 weeks