Use a single digit times a power of 10 to express the number 866,214,000,000

Antonio made a scale model of a building. the model's scale is 1 inch to 235 feet and its height is 3.5 inches. what is the exact height of the actual building? enter your answer in the box.

One positive number is 9 more than twice another. if their product is 95, find the numbers

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