DestinyofE

6g of a contaminant is introduced instantaneously 5m along the cross section of a pipe that is 10m long and has a 1m2 cross sectional area. Water is being very slowly pumped through from one side and out the other at 5 x 10^-5 m/s and Dm = 3 x 10^-8 m2/s a.) At what time does the CENTER of the contaminant patch reach the end of the pipe? b.) What is the MAXIMUM CONCENTRATION at that time? c.) Where is the TRAILING EDGE (assuming the width of patch is 4sq(2Dmt) located after 5 x 10^5 s? Note: I primarily need help on part A, i can do the rest on my own but I'm so lost on how to figure out the time in part A.