The given expression is
.
We need to simplify the given expression.
<h3>What is a rational number?</h3>
In mathematics, a rational number is a number that can be expressed as the quotient or fraction p/q of two integers, a numerator p and a non-zero denominator q.
Now group the rational numbers 



Therefore, the simplified value of the given expression is
.
To learn more about the rational numbers visit:
brainly.com/question/17450097.
#SPJ1
I might be wrong but I think it's 50 minutes.
$0.10 x 50min = $5
$20 + $5 = $25
$0.20 x 50min = $10
$15 + $10 = $25
So, it's 50 minutes.
Answer:

Step-by-step explanation:
Find r :
C=2πr
280=2(3.14)r
r=280/2(3.14)
r=44.6cm
find area :
A=πr²
A=3.14(44.6)²
A=6246 cm²
Answer : 4)6,246
B because pie radius square = area of a circle