1. The problem shows a chain of logical implications connecting different mathematical expressions related to speed, distance, and time. 2. The first expression is $v = \frac{c}{t}$, which defines speed $v$ as distance $c$ divided by time $t$. 3. The arrow $\Rightarrow$ suggests that if this is true, then the next expression $ct = d$ follows, interpreting $d$ as the distance covered in time $t$ with speed $c$. 4. The next arrow leads to $d = ct$, which is just the rearranged form indicating distance equals speed times time. 5. The following step $\Rightarrow ct = d$ repeats the prior equivalence. 6. The final step $\Rightarrow l = ct$ introduces $l$, which can be treated as another notation for length or distance equivalent to $ct$. Hence, this chain shows the direct proportionality between distance, speed, and time, rewriting the same relation in multiple equivalent ways.