An object is moving away from you while making a sound. What is perceived about the pitch of the sound?

It is perceived to be higher.

It is perceived to be fluctuating.

It is perceived to be lower.

It is perceived to be unchanged.

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.

Which statement best describes what happens when molecular compounds melt

Use the half-reactions of the reaction au(oh)3 + hi -> au +i2 +h2o to answer the questions