What is the difference between vertical integration and related diversification?.

Why do interests rates on loans to be lower in a weak economy than in a strong one

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?

0if x and y vary inversely and y=6 as x=7, what is the constant of variation?