PLEASE PLEASE HELP I DON’T UNDERSTAND I provided the pictures to all of the questions. I’m usually good with math but this is confusing

Apatient is given 50 mg dose of medicine the medicines effectiveness decreases every hour at a constant rate of 40% what is the exponential decay function that models this scenario how much medicine will be left in the patients system after 2 hours

Arectangle with an area of 47 m² is dilated by a factor of 7. what is the area of the dilated rectangle? enter your answer in the box. do not leave your answer as a fraction.

Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)