Answer :
It will be 25cm long
Since it growing 10cm every 2 years it must be growing 5cm every year
10/2=5/1
To find total growth in 5 years multiply the cm it grows every year by the number of years so
5yearsX 5cm
=25cm
find the unit rate .unit rate =5:1 multiply 1x5 and 5x5 and you will get 25:5 so 25 would be your answer