Answer:
Their mass at the start was 400 kg.
Step-by-step explanation:
Given:
The tyres on a car during a grand prix race are reduced in mass by 3%. Their mass is 388 kg at the end of the race.
Now, to find the mass at the start.
<u>Let the mass at the start be
.</u>
According to question:

⇒
⇒
⇒
<em>Dividing both sides by 0.97 we get:</em>
⇒
Therefore, their mass at the start was 400 kg.
Area = π.R² AND CIRCUMFERENCE = 2π.R
Let's calculate R (radius):
452.16 = π.R² → R² = 452.16/π → R² = 143.92 And R = √143.92 →R = 12 m
CIRCUMFERENCE = 2π.R = 2π.12 = 24 π = 75.39 84 (Answer D)
Answer:
= 99999999999999 lololololol
You Have To Solve The Variables