What combinations of up and down did quarks combine to make the proton? A. Down + down + down
B. Up+Up+ down
C. Up+Up+Up
D. Up+down+down
E. Up+down

You encounter a solution that is acidic and you decide to test it by adding a small amount of a strong acid. the ph lowers slightly but is approximately unchanged, and still remains acidic. what can you say about the solution? a. it is a buffer solution. b. it is not a buffer solution it is a strong acid solution. d. the solution has been neutralized. e. the solution has excess acid present

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?

The excretory system,need answers for all: )