The best surface to run on is one that's
a. as hard as possible so that it adds more stability to your foot.
b. uneven so that the tendons and ligaments in the ankles and knees are strengthened.
c. smooth and soft so that it can cushion the stresses of running,
d. hilly so that you can improve your cardiovascular endurance.

C, smooth and soft so it can cushion the stresses of running

The best surface for a beginner to run on is smooth and soft so that it can cushion the stresses of running. For a more advanced runner, hills could be beneficial in improving their training and cardiovascular endurance.

Explanation:

the answer for this worksheet are the following:

1.            u

2.            e

3.            i

4.            o

5.            e

6.            h

7.            l

8.            e

9.            s

10.    y

11.    d

12.    e

13.    v

14.    r

15.    f

16.    r

17.    l

18.    c

then the given to crack is 6 12 3 9 15 1 17 7 10 14 8 18 4 13 2 16 5 11

the answer is he is fully recovered