Ben swims 50,000 yards per week in his practices. given this amount of training, he will swim the 100-yard butterfly in 51.5 seconds and place 10th in a big upcoming meet. ben's coach calculates that if ben increases his practice to 60,000 yards per week, his time will decrease to 46.4 seconds and he will place 7th in the meet. if ben practices 70,000 yards per week, his time will be 44.6 seconds and he will win the meet. in terms of ben's time in the big meet, what is his marginal productivity of the number of yards he practices?

Which equation represents the line that passes through the points and (4, 10) and (2, 7)? y = 3/2x - 11y = 3/2x +4y = - 3/2x + 19y = - 3/2x + 16

Someone answer this asap rn 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)) =

Daniel expanded the expression as shown below -2(-8x-4y+3/4)=-10x-8y-11/4 what errors did he make? check all that apply