plutonium 240 decays according to the function Q(t)=Q0e^-kt where Q represents the quantity remaining after t years and k is the decay constant,0.00011 to the nearest 10 year how long will it take 36 grams of plutonium -240 to decay to 12 grams

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.