In still water Derek can paddle his canoe at 6.5km/h. On a river the canoe travels faster downstream than upstream because of the current. In the morning Derek travels upstream and takes 5 hours and then in the afternoon Derek travels downstream the same distance and takes 2 hours. What is the speed of the current? Answer to the nearest tenth.

What value of x is in the solution set of –5x – 15 > 10 + 20x?

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?

1- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis.2- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in the first question?