Tina and her family live on a farm. each year

(200π - 12)ft

or

616.32 ft

Step-by-step explanation:

Given in the question,

there are four circle around which corn will be planted.

radius of first circle = 10 ft

radius of second circle = 20 ft

radius of third circle = 30 ft

radius of fourth circle = 40ft

circumference = 2πr

First circle

2π(10)-3

20π -3

Second circle

2π(20)-3

40π-3

Third circle

2π(30)-3

60π-3

Fourth circle

2π(40)-3

80π-3

Add them up

80π - 3 + 60π - 3 + 40π - 3 + 20π - 3

(200π - 12)ft

or

616.32 ft