Question 1 Parent-Care is a budding business enterprise specialising in childcare and growth. It has a website with interesting information and advice on nutrition for children, safety, health supplements, health and recreation for children, parenting tips and children's education. Since its establishment three years ago, Parenz-Care has garnered quite a following among young parents. The Q & A section in its website is especially popular with parents posting questions varying from nutrition for children to ways to handle hyperactive kids and educational concerns in Singapore's stressful school environment. Recently Parenz-Care has engaged your market research firm to help conduct a telephone interview exercise. It is interested to solicit views from its customer base as well as from the public. The survey feedbacks will be used to improve its products and services, particularly in the areas of child nutrition, parenting skills and upcoming tuition services. Three family types have been identified for the interviews, viz: 1 . One-child family 11 . Two-child family ili. Three-child family The interview questionnaire for each family type is not the same in contents although there are some core questions asked for each family type. The contents for the three-child family questionnaire are more complex and comprehensive which requires more time (and hence cost) to conduct compared with the other two questionnaires. Parenz-Care's request for your firm's services comprises the following requirements: The telephone surveys will be conducted over a period of 3 months. (1) Both Morning-interviews (9am to 12.00 noon) and Evening-interviews (6pm to 9.00pm) are to be conducted on weekdays while interviews on Saturdays are limited to mornings only (9am to 12.00 noon). (2) An interview is deemed completed only if the questionnaire involved is completed. (3) The total number of households for the entire survey exercise must be at least 2200. (4) The cost per interview for the different family types is given in the table below