A hectare is equal to 2.471 acres. A land developer buys a hectare of land to build homes. Each home will be built on 0.25 acres of land. How many homes can the land developer build on the hectare of space?

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?