A certain motorcycle manufacturer has been building motorcycles for 98 years. Over that period, production has increased steadily at an annual rate of 4%, so that the production rate, in motorcycles/year, after t years was r(t)=A⋅1.04^t
where A is a constant representing the initial production rate. What fraction of their total production was built during the last 10 years? Your answer should be a number between 0 and 1.