How do you find the sum of the n^th row and all it's previous rows using pascals triangle

Find the simple interest earned to the nearest cent for each principal, interest rate, and time 735 7% and two and a half years

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?

Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.