Answer:
1.6 cm 
 0.625 day
Explanation:
We are given that the grass in Jamie's yard grew 16 cm in 10 days. 
 
It was growing at constant rate. 
 
We have to find number of days taken by the grass to grow 1 cm and how many cm grass grow in one day. 
 
In 10 days , grass grow=16 cm 
 
In 1 day, grass grow= 
 
Grass takes time to grow 16 cm=10 days 
 
Grass takes time to grow 1 cm==0.625 days 
 
Hence, the grass grow 1 cm in 0.625 days and the grass grow 1.6 cm in one day.