Suppose $500 is invested in an account that pays 4.75% interest compounded continuously (a) find a formula for the amount in the account at any time t
(b) when will the amount in the account be double the initial value?

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.