If there is 7018 mm, what is the metric unit for 7.018?

What number should be added to the expression x^2+3x+ in order to create a perfect square trinomial? 3/2 3 9/4 9

Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5

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?