How do you do #9? ? i know what the answer is but idk how to get to it

In a sample of 200 residents of georgetown county, 120 reported they believed the county real estate taxes were too high. develop a 95 percent confidence interval for the proportion of residents who believe the tax rate is too high. (round your answers to 3 decimal places.) confidence interval for the proportion of residents is up to . would it be reasonable to conclude that the majority of the taxpayers feel that the taxes are too high?

Antonia and carla have an equivalant percentage of green marbles in their bags of marbles. antonia has 4 green marbles and 16 total matbles. if carla has 10 green marbles , how many total marbles does carla have

What is the number 321,000,000 in scientific notation? also what is the number? ?