Anna is building a figure that has three columns of unit cubes. The first column is shown below. The other two columns each have four fewer unit cubes than the first column. What is the volume in cubic units, of Anna’s figure?

In the diagram, the ratio of ab to ae is (1/2) . what is the ratio of the length of to the length of ?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?

Prove that 16^4-2^13-4^5 is divisible by 11.