Find the derivative through the limiting process--i'm stuck

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Anew landowner is interested in constructing a fence around the perimeter of her property. her property is 1,080√30 feet wide and 500√20 feet long. what is the perimeter of the property? (recall that the perimeter is the sum of each side of a shape or boundary). a 1,580√40 feet b. 5,320√5 feet c. 3,160√20 feet d. 10,640√5 feet

The half-life of a certain material is 0.004 second. approximately how much of a 20-gram sample will be left after 0.016 second? a. 5 grams b. 16 grams c. 0.32 gram d. 1.25 grams

Georgia needs to buy flea treatment for her dog. pet store 1 is offering the flea treatment for 40 percent off plus an additional 25 percent off their regular price of $33. pet store 2 is offering the same flea treatment for 55 percent off plus an additional 5 percent off their regular price of $34. which location is offering the better price and how much cheaper is it? the flea treatment is $0.31 cheaper at pet store 2. the flea treatment is $1.05 cheaper at pet store 2. the flea treatment is $2.05 cheaper at pet store 1. the flea treatment is $2.36 cheaper at pet store 1.