Step-by-step explanation:
We have a diameter and vertical angles so
231.
180+51=231
Yes a square is a parallelogram.
Answer:

Step-by-step explanation:
18 min = 0.3 h
Car 1 started 0.3 h before Car 2.
Let t = time of Car 2. Then
t + 0.3 = time of Car 1
Distance = speed × time, and both cars travel the same distance. Then

Check:

OK.
The answer is
![r= \sqrt[3]{GMT^{2}/4 \pi^{2}}](https://tex.z-dn.net/?f=r%3D%20%5Csqrt%5B3%5D%7BGMT%5E%7B2%7D%2F4%20%5Cpi%5E%7B2%7D%7D%20)

Move

to the other side of the equation:

Rearrange:

Since
![x^{3}= \sqrt[3]{x}](https://tex.z-dn.net/?f=%20x%5E%7B3%7D%3D%20%5Csqrt%5B3%5D%7Bx%7D%20%20)
, then
You multiply 19 × 2.54 to convert it to cm