$16.$ A block sliding with velocity $\backslash (\backslash$mathrm$\{$v$\}>0\backslash )$ along a frictionless floor hits a spring at time $\backslash ($ t$=0\backslash )($configuration $1).$ The spring compresses until the block comes to a momentary stop $($configuration $2).$ Finally, the spring expands, pushing the block back in the direction from which it came. The positive $\backslash ($ x $\backslash )$ direction is to the right. Besides time, what other quantities are equal to zero when the block hits the spring $($configuration $1)?$

a$.$ position only

b$.$ velocity only

c$.$ position and velocity

d$.$ position and force

e$.$ velocity and force

$17.$ A block sliding with velocity $\backslash ($ v$>0\backslash )$ along a frictionless floor hits a spring at time $\backslash ($ t$=0\backslash )($configuration $1).$ The spring compresses until the block comes to a momentary stop $($configuration $2).$ Finally, the spring expands, pushing the block back in the direction from which it came. The positive $\backslash ($ x $\backslash )$ direction is to the right. What might graph $\backslash ($ C $\backslash )$ represent?

a$.$ position vs$.$ time

b$.$ velocity vs$.$ time

c$.$ force vs$.$ time

d$.$ force vs$.$ position