What is 3x-5=3x-c? it says describe the values of c

It took alice 5 5/6 hours to drive to her grandparents' house for . on the way home, she ran into traffic and it took her 7 3/8 hours. how much longer did the return trip take? write your answer as a proper fraction or mixed number in simplest form. the trip home took __hours longer. ?

45% of the trees in a park are apple trees. there are 27 apple trees in the park. how many trees are in the park in all?

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)