$A$ car covers the first half of the distance between two places at $40 \text{ km/h}$ and the second half at $50 \text{ km/h}$. The average speed of the car is (in $text{ km/h}$)

Is the statement "$A$ particle can have zero speed but non-zero velocity" true or false? Explain.

$A$ body covers the first one-third of the distance with a velocity of $20 \, m/s$,the second one-third with a velocity of $30 \, m/s$,and the last one-third with a velocity of $40 \, m/s$. The average velocity is nearly........$m/s$.

$A$ car travels from point $A$ to point $B$ with a speed of $40 \ km/h$ and returns from $B$ to $A$ with a speed of $60 \ km/h$. What is the average speed of the car for the entire journey (in $km/h$)?

$A$ car moves from $A$ to $B$ with a speed of $30 \ km/h$ and from $B$ to $A$ with a speed of $20 \ km/h$. What is the average speed of the car (in $km/h$)?

Define velocity. Define average velocity.