the paralyzed veterans of america receives donations every year. they want to understand which of its donors are more likely to donate again, so they take a random sample of 1400 donors and compile them in to the pva small.xlsx data set. they use the response variable as time.between.gifts. the factors of interest are: own.home., num.children, sex, and total.wealth. what is the first split? group of answer choices num.children<2, num.children>