Please help this is a big grade please

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

20 pts ‼️ an unmanned spacecraft travels to mars. mars has a lower strength of gravity than earth. where in the image is the spacecraft’s weight the greatest?

Determine the ph of 0.10 m nh3 solution. nh3 is a weak base with a kb equal to 1.8 x 10-5 round answer to nearest whole number.