The dataset lowbwt contains information recorded for a sample of 100 low birth weight infants born in two teaching hospitals in Boston. Measurements of systolic blood pressure are saved under the variable named sbp, while indicators of gender-- 1 indicating a male and 0 indicating a female-- are saved under the variable name sex.

1. Compute a 95% confidence interval for the true mean systolic blood pressure of male low birth weight infants.

lowbwt (2)
sbp	sex	tox	grmhem	gestage	apgar5
43	1	0	0	29	7
51	1	0	0	31	8
42	0	0	0	33	0
39	0	0	0	31	8
48	0	1	0	30	7
31	1	0	1	25	0
31	1	1	0	27	7
40	0	0	0	29	9
57	0	0	0	28	6
64	0	1	0	29	9
46	0	0	0	26	7
47	0	0	1	30	6
63	0	0	0	29	8
56	0	0	0	29	1
49	1	0	0	29	8
87	1	0	0	29	7
46	0	0	0	29	8
66	0	0	0	33	8
42	0	1	0	33	8
52	0	0	0	29	7
51	1	0	0	28	7
47	0	0	0	30	9
54	1	0	0	27	4
64	1	0	0	33	9
37	0	0	0	32	7
36	1	1	0	28	3
45	0	0	1	29	7
39	1	0	0	28	7
29	0	0	0	29	4
61	0	0	0	30	3
53	1	0	0	31	7
64	0	0	0	30	7
35	0	0	0	31	6
34	1	0	0	29	9
62	0	0	0	27	7
59	0	0	0	27	8
36	1	0	0	27	9
47	0	0	0	32	8
45	1	0	1	31	2
62	0	0	1	28	5
75	1	1	0	30	7
44	1	0	0	29	0
39	1	0	0	28	8
48	0	0	1	31	7
43	0	1	0	27	6
19	0	0	1	25	4
63	1	0	0	30	7
42	1	0	0	28	6
44	0	0	0	28	9
25	0	0	0	25	8
26	0	0	0	23	8
27	1	0	0	27	9
35	1	0	0	28	8
40	1	0	0	27	7
44	0	0	0	27	6
66	1	0	0	26	8
59	0	0	0	25	3
24	0	0	0	23	7
40	0	0	1	26	3
49	0	0	0	24	5
53	1	1	0	29	9
45	0	0	0	29	9
50	1	0	1	27	8
64	1	0	0	30	7
48	0	0	0	30	6
48	0	0	1	32	4
58	0	1	0	33	7
67	0	0	0	27	8
40	0	0	1	31	8
48	0	0	0	26	8
36	1	0	0	27	5
44	1	0	0	27	6
53	0	1	0	35	9
45	0	1	0	28	6
54	1	0	0	30	8
44	1	1	0	31	2
42	1	0	0	30	5
50	0	0	0	27	0
48	0	0	0	25	5
29	0	0	1	25	5
30	0	0	1	26	2
36	0	0	0	29	0
44	0	0	0	29	0
46	0	1	0	34	9
51	1	1	0	30	4
51	1	0	0	29	5
43	1	1	0	33	7
48	1	0	0	30	5
52	1	0	0	29	8
43	1	0	0	24	6
42	1	1	0	33	8
48	1	0	1	25	5
49	0	1	0	32	8
62	1	1	0	31	7
45	1	0	0	31	9
51	0	1	1	31	6
52	1	0	0	29	8
47	1	1	0	32	5
40	0	1	0	33	8
50	0	0	0	28	7