Lindy wants to buy grapefruit, and the cost of a grapefruit is $0.5. Form an equation for the cost of x number of grapefruits and identify the independent and the dependent variables. A).x = $0.5cost; Independent variable = cost, Dependent variable = x. B).Cost = $0.5x; Independent variable = x, Dependent variable = Cost. C).Cost = $0.5x; Independent variable = cost, Dependent variable = x. D).x = $0.5cost; Independent variable = x, Dependent variable = cost. 2. A photo studio charges $0.50 per copy. If n = number of copies and C = total cost, form an equation with n and C. A).C = 0.50 + n B).C = n – 0.50 C).C = n ÷ 0.50 D).C = 0.50n 3. Joe’s family must travel x miles to visit their grandparents. If Joe travels 40 miles per hour, how many hours (y) will he take to meet his grandparents? A).y = x/40 B).y = 40x C).y = 40 + x D).y = 40 4. A photo studio charges a fixed amount of $2 plus $0.50 per copy. Let n = number of copies and C = total cost. Identify the dependent and independent variables. A).n = dependent variable, C = independent variable B).Both n and C are dependent variables. C).Both n and C are independent variables. D).n = independent variable, C = dependent variable 5. A development psychologist is testing the hypothesis that children in first grade know more words in the English language than children in Kindergarten. To test this, she sits in on two classes (one first grade, the other Kindergarten) and counts the average number of words children in each class speak. She then compares the counts. Identify the independent and the dependent variables. A).Independent variable = Grade and dependent variable = Number of words. B). variable = Grade and independent variable = Number of words. C).Both grade and number of words are independent variables. D).Both grade and number of words are dependent variables. 6. An airplane takes off at a rate of 20 miles in 1 minute. Form an equation using the distance and time taken. A).d = 20t B).d = 20 C).d = -20t D).d = 20/t