The figure below models a particles velocity as a function of time. Use this figure to answer the following questions $(13,14,15)$

$13.$ Of the following segments, where does the particle's acceleration have the greatest magnitude.

a$.\frac{?}{\text{b}\text{a}\text{r}}(A)$

b$.\frac{?}{\text{b}\text{a}\text{r}}(B)$

c$.\frac{?}{\text{b}\text{a}\text{r}}(C)$

d$.\frac{?}{\text{b}\text{a}\text{r}}(D)$

e$.$ None

$14.$ Of the following segments, where is the particle slowing down?

a$.\frac{?}{\text{b}\text{a}\text{r}}(A)$

b$.\frac{?}{\text{b}\text{a}\text{r}}(B)$

c$.\frac{?}{\text{b}\text{a}\text{r}}(C)$

d$.\frac{?}{\text{b}\text{a}\text{r}}(D)$

e$.$ None

$15.$ Of the following segments, where does the particle have constant acceleration?

a$.\frac{?}{\text{b}\text{a}\text{r}}(A)$

b$.\frac{?}{\text{b}\text{a}\text{r}}(B)$

c$.\frac{?}{\text{b}\text{a}\text{r}}(C)$

d$.\frac{?}{\text{b}\text{a}\text{r}}(D)$

e$.$ None