When my father was 31 i was 8. now he is twoce as old as me. how old am i? can u explain to me this question

Find the number of liters in 12.8 gal of gasoline. round to the nearest hundredths

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?

What is the total surface area of this square pyramid?