Asquare has a perimeter of 20 in what is the length of each side

There are 20 children in the cast of a class play and 8 of the children are boys of the boys 4 have a speaking part in the play and of the girls 8 do not have a speaking part in the play if a child from the cast of the place chosen at random what is the probability that the child has a speaking part

The table shows the distance traveled over time while traveling at a constant speed.

Need solving this second acceleration problem.