Regular exercise can help a person lower their resting heart rate. Suppose an individual's resting heart rate, in beats per minute, is modeled by the function f(x) = -0.1x3 + 0.6x2 + 85 after x weeks of regular exercise.
How many weeks of exercise are necessary to lower the individual's resting heart rate below 70 beats per minute?

7 weeks
8 weeks
9 weeks
10 weeks

Someone answer asap for ! a discount store’s prices are 25% lower than department store prices. the function c(x) = 0.75x can be used to determine the cost c, in dollars, of an item, where x is the department store price, in dollars. if the item has not sold in one month, the discount store takes an additional 20% off the discounted price and an additional $5 off the total purchase. the function d(y) = 0.80y - 5 can be used to find d, the cost, in dollars, of an item that has not been sold for a month, where y is the discount store price, in dollars. create a function d(c(x)) that represents the final price of an item when a costumer buys an item that has been in the discount store for a month. d(c(x)) =

On the first of each month sasha runs a 5k race she keeps track of her times to track her progress her time in minutes is recorded in the table

Urgent! 20 points! here is a you are the new manager at trusty goods wholesale produce. you need to figure out how to adjust the amount of produce in your notes after the events of the day: you got 5 more crates of bananas someone returned 2 crates of apples a worker dropped a crate of grapes (oh no! , you had to throw them out) you sold a crate of bananas you sold 5 crates of apples can you write an expression to describe your day using: "a" for crates of apples "b" for crates of bananas and "g" for crates of grapes? make sure the expression is in simplest form question 2 (3 points) explain your steps using sentences.