A winery has a barrel to hold chardonnay. An inlet pipe can fill the barrel in 18 hours, while an outlet pipe can empty the barrel in 21 hours. How many hours would it take to fill the barrel if both the inlet and outlet pipes are open

answer 1 : option "c"

answer 2 : option "d"

answer 3 : option "b"

answer 4 : option "d"

answer 5 : option "b"

answer 6 : option "a"

answer 7 : option "c"

answer 8 : option "d"

answer 9 : option "c"

answer 10 : option "d"

answer 11 : option "c"

answer 12 option "b"

answer 13 option "c"

answer 14 option "c"

answer 15 option "d"

answer 16 option "a"

answer 17 option "b"

answer 18 option "c"

answer 19 option "a"

answer 20 option "a"

answer 21 option "c"

d

i agree because i see the other persons thinking is clear

there were only 2 presidents that were under the age of 45. theodore roosevelt, and jfk, that makes 5%