PLZ help! An explanation would be great also :)

The number of fish in a lake can be modeled by the exponential regression equation y=14.08 x 2.08^x where x represents the year

The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?