The mass of a radioactive substance follows acontinuous exponential decay model, with a decay rate parameter of1%per day. A sample of this radioactive substance was taken four days ago. If the sample has a mass of3 kg today, find the initial mass of the sample. Round your answer to two decimal places.

Note:This is acontinuousexponential decay model.

And though the decay rateparameteris1%

per day, the actual decay isnot1% each day.

____ kg