Question $3$

$[10/100$ marks$]$

Two sets of students are collecting traffic data at two sections, $$ and $yy,$ of a highway $450m$ apart.

Observations at $$ show that five vehicles passed that section at intervals of $3,4,3,$ and $5sec,$ respectively. If the speeds of the vehicles were $80,70,60,55,$ and $50k\frac{m}{h}$ respectively, draw a schematic showing the locations of the vehicles $20sec$ after the first vehicle passed section $.$ Also determine:

$($a$)$ the time mean speed; $[4/10]$

$($b$)$ the space mean speed; $[3/10]$

$($c$)$ the density on the highway. $[3/10]$