What do the kidneys do if ph levels are too high or too low in the blood?

a. they release substances into the blood to neutralize the ph levels.
b. they filter the blood so that all substances in the blood are flushed out of the system.
c. they do nothing; a high or low ph cannot be corrected once it impacts the blood.

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination.at the turning point, how far is the second student from the destination?