On a recent trip, juan started at an elevation of 1200 feet above sea level. he descended into a valley 20.4 feet below sea level. which of the following shows one way to calculate how many feet he descended in all? a. -20.4–(-1200) b. 1200–20.4 c. -20.4+1600 d. 1200–(-20.4)

A would be the correct answer because he is up in elevation so that makes the 1200 positive and he goes down 20.4 which is negative and is goes that far down!!

hope this helps

D is the correct answer because you would subtracts what he descended from where he started in order to find out how many feet he descended in all.

the total estimated nappy use.=10,500,000

step-by-step explanation:

given that on an average the average baby uses 3528 napkins.

in a particular year 2014, the number of births were 299697 in new south wales.

rounding off the number of births to the nearest hundred thousand we have

no of birtsh = 300000

also rounding off the average usage to nearst thousand we get

average use of a baby = 3500

hence total number of nappy estimated to be used = 3500x300000

= 10,500,000

answer is 10,500,000 nappies