An oil refinery is located on the north bank of a straight river that is 2 km wide. a pipeline is to be constructed from the refinery to storage tanks located on the south bank of the river 10 km east of the refinery. the cost of laying pipe is$200,000/km over land to a point p on the north bank and $400,000/km under the river to the tanks. to minimize the cost of the pipeline, how far from the refinery should p be located? (round your answer to two decimal places.)

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?