1.8 Smoking habits of UK residents. A survey was conducted to study the smoking habits of UK residents. Below is a data matrix displaying a portion of the data collected in this survey. Note that "{" stands for British Pounds Sterling, "cig" stands for cigarettes, and "N/A" refers to a missing component of the data.58 sex age marital grossIncome smoke amt Weekends amt Weekdays Female 42 Single Under $2,600 Yes 12 cig/day 12 cig /day Male 44 Single E10,400 to $15,600 No N/A N/A Male 53 Married Above $36,400 Yes 6 cig / day 6 cig/ day 1691 Male 40 Single C2,600 to $5,200 Yes 8 cig / day 8 cig /day (a) What does each row of the data matrix represent? (b) How many participants were included in the survey? (c) Indicate whether each variable in the study is numerical or categorical. If numerical, identify as continuous or discrete. If categorical, indicate if the variable is ordinal