Bret and Cindy took different routes to travel from Point A to Point E. Bret took the route along A, B, C, D, and E. Cindy took the route along A, F, and E and reached the destination in 2 hours. Their routes are shown. If Bret's average speed was twice Cindy's average speed, what was Bret's average speed?

3 miles per hour
6 miles per hour
8 miles per hour
9 miles per hour

Answer asap need to be answered by wednesday morning explain how a buffer works, using an ethanoic acid / sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.