6. Which is the true algebraic expression for "the product of a number and 11 is 77"? A n + 11 - 77 B. n - 11 = 77 C. nx 11 = 77 D. n + 11 = 77 7. Which of the following questions below will best complete the story problem in the box? Marina weighs half as much as her mother who weighs 60 kilograms. A. How many kilograms does Marina weigh? B. How much kilograms does mother weigh? C. How many kilograms is half as much as mother weigh? D. How much longer does mother weigh? 8. A car covered a distance of 550 km for 5 hours. What is its average speed? A. 100 km/p B. 105 km/h C. 110 km/h D. 115 km/h 9. Three times the sum of the number and four is represented in an algebraic expression as A. 3 (n + 4) B. 3 (n-4) C. 3(nx4) D. 3 (n4)​