Hello!
First you have to count how many tallies the car went 9 tallies
Multiply the amount of tallies by how far they represent
9 * 0.8 = 7.2 meters
The car when 7.2 meters in half a second so we double this to get how fast it was going a second
7.2 * 2 = 14.4
The answer is 14.4 m/s
Hope this helps!
