I need help on this PLS HELP ILL GIVE YOU BRAINLIST

(a) average speed =

total distance = 1.7 km = 1700m

total time = 50 s

= 34 m/s

(b) total distance = area below graph

total distance = 1700 m

*the area below graph is a trapezium shape , so us the trapezium formula :

1/2 × ( total length of 2 parallel sides ) × height

1700 m = 1/2( 30 + 50 )(k)

1700 = 1/2 × 80k

1700 = 40k

1700/40 = k

k = 42.5

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.

the eight graders whould be the answer

step-by-step explanation: could you give me 5 stars