假设病人生存时间服从指数分布, 以此参数估算病人存活超过2年的概率.请问这类型问题R的代码怎么写啊，有人知道么
Survival
1.8
1.3
6.6
1.4
6.4
10.7
2.2
39.8
7.3
2.9
3.6
5.7
2.1
2.9
2
7.5
20.9
6.1
13.6
0.2
14.2
5
11
10
26.5
16.5
8.8
2.4
0.4
11.3
11.7
2.3
6.6
18.9
9.9
12.3
2.6
9.8
19.9
11.2
1.7
2.2
4.8
2.2
7.6
4.9
35.8
5.4
39.2
0.2
3.7
3.4
0.8
2.8
8.8
2.7
0.4
9.7
2.7
0.5
3.5
6
2.8
15.9
10.4
1.4
0.7
1.8
49.5
0.9
16.8
1.9
1.7
5.9
10.1
5.2
4.3
23
38.7
51.5
4
4.5
34
3.6
1.6
2.7
8.4
8.8
15.7
4.8
7.4
12.3
0.5
5.1
5
5.2
4.1
33.9
10.3
2.8
0.1
0.6
27.7
0.7
13.9
5.4
7.7
14.5
0.7
18.2
14.1
5.3
2.1
11.4
8.1
17.3
3.2
6.8
1.7
2
4.9
0.8
0.8
5.8
9.5
33.3
4.5
4.1
2.9
2.7
3.2
12.7
0.1
21.3
3.1
6.3
21.3
39.1
6.3
14
0.8
21.1
8.9
5.1
1.5
0.3
3.8
13.1
0
14.1
1.7
1.1
0.5
2.4
17
20.4
5.2
4.4
11.6
8.2
5
5.2
2.3
30
12.9
19.8
10.3
21.5
35.9
7.5
19.6
1.6
10.2
7.5
18.1
22
15.5
5.7
0.2
8.2
13.2
0
3.5
0.4
11.8
0.4
7.5
0.9
1.5
27.8
28.1
2
2.8
5.6
0.4
3.2
0.6
6
1.6
3.4
1.2
0.4
13.7
11.4
0.4
1.1
3.3
13.2
0.9
0.1
16.7
10
1.4
5.3
13.3
1.5
4.5
11.5
2.7
14.3
8.5
1.6
9.6
1.4
1.4
11.5
25.1
11.7
15.4
13.2
5.6
16.3
11.3
0
2.2
32.3
0.6
26.2
6.3
1.6
28.7
18.2
20.4
32.6
23
17.5
11.1
30.6
17.5
0.4
4.4
1.8
8.2
7.7
6.7
0.3
28.2
1.6
3.5
28
1.6
11
1.5
1.8
10.9
27.7
3.1
4.2
3.8
2.2
11.5
24
1.3
3
8
0.6
0.2
9.6
3
30.6
0.1
4.5
3
11.8
13.4
2.1
2.7
16.8
4.4
2.6
12.1
5.2
4.9
17.1
1.3
27.4
21.2
7
34.2
1.1