Step-by-step explanation:
The formula for calculating a circle's circumference is πd, where π is an irrational number (3.14....) and d is the diameter of the circle.
In the circle with diameter 19.5cm, the circumference is around 3.14 * 19.5cm = 61.23cm. (A)
You have a lot of questions here, I can help you with a few of them.
When you simplify the polynomials, you put together all of the terms that have the same degree. That means the variables have the same exponents. The number of terms are the items separated by plus and minus signs.
Here are the answers for the first three:
1)

2)

3)
Answer: 188 cm² I think that's it
Step-by-step explanation:
At first he had 72 then he gave 27 to his neighbor ( 27 subtract 72 = 45) and then he gave 15 to his brother ( 45 subtract 15 = 30)
he had 30 tomatoes left.
Answer:
72x3 or 6x9 sorry if wong
Step-by-step explanation: