The half life of a certain substance is about 4 hours. the graph shows the decay of a 50 gram sample of the substance that is measured every hour for 9 hours.

which function can be used to determine the approximate number of grams of the sample remaining after t hours?

a
y = 50(0.85)x

b
y = 25(0.15)x

c
y = 50(0.15)x

d
y = 25(0.85)x

Which rational number could be graphed between -4 and -5

John checked his watch and said that it is thursday, 7 am. what will the day and time be 2006 hours plzzz i will give you 100 points

Bella want to know what the students at her school think of her show. which is the best group to survey to find this information a. go to the mall and ask all of the students she recognizes from school b. ask her viewers to call in durning an episode of the show c. get a list of students at her school from the office and use a random number generator to pick 30 of them d. get a list of students at her school from the office and pick the first 30 students on the list