The number of bacteria in a certain population increases according to a continuous exponential growth model, with a growth rate parameter of 7.1 % per hour. how many hours does it take for the size of the sample to double?

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.