The half life of a certain tranquilizer in the bloodstream is 30 hours. How long will it take for the drug to decay to 80% of the original dosage

Pyotr tchaikovsky sporting goods operates on a 45% overhead based on the selling price, which results in an overhead of $65.34 on the newest version of an air hockey game set. if the air hockey game set costs pyotr tchaikovsky sports $49.32, find the selling price, the markup, and the net profit.

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?

Margie is practicing for an upcoming tennis tournament. her first serve is good 20 out of 30 times on average. margie wants to know the estimated probability that her first serve will be good at least four of the next six times she serves. how could she design a simulation for this scenario?