Can someone me i need this answer urgently but i don't know the first section

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

Louis wants to carpet the rectangular floor of his basement.the basement has an area of 864 square feet.the width of the basement is 2/3 it's length. what is the length of louis's basement

Which is the solution to the inequality? 2 3/52 1/15 b< 3 2/15 b> 3 2/15