A particle moves along a straight line, and its position at time t seconds is described by s(t). Which of the following expressions represents the particle’s instantaneous velocity v(t)?
a) Δts(t+Δt)−s(t) for a fixed non-zero Δt
b) ts(t)−s(0)
c) s′(t)
d) 2Δts(t+Δt)−s(t−Δt) for a fixed non-zero Δt