When U. S. farmers in the Southwest irrigate their land, salt in the ground soil leaks into the Colorado River. The Colorado River has become so salty that Mexican farmers further down the river cannot irrigate their own land and Mexican crops have been devastated. This situation constitutes a negative externality because: a. U. S. farmers consider only their external costs in their decision making.
b. Mexican farmers consider only their private costs in their decision making.
c. U. S. farmers consider only their private costs in their decision making.
d. The social cost of irrigation exceeds the social benefits.

Asap 25 pts + brainlest to right/best answer

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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)) =