4. A recent survey found that 68.6% of the population own their homes. In a random sample of 180 heads of households, 108 responded that they owned their homes. At the a =0.01 level of significance, does that suggest a difference from the national proportion? 5. Please state your opinion (true or false) on the following two statements and explain why. A. Assume other conditions unchanged, lower confidence levels will produce wider confidence intervals. B. Assume other conditions unchanged, If you increase sample size, the width of confidence intervals will increase. 6. Researchers surveyed a group of 273 randomly selected teen girls living in Massachusetts (between 12 and 15 years old). After four years the girls were surveyed again. Sixty-three said they smoked to stay thin. Is there good evidence that more than thirty percent of the teen girls smoke to stay thin