Write about using a unit cube to measure length

Write and solve a real word problem that involves determining distance on a coordinate plane

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)

Arectangle plot measure 20ft. by 30ft. a 3-ft.-wide sidewalk surrounds it. find the area of the sidewalk.