Answer:
<h2>12.56 m</h2>
Step-by-step explanation:
The formula of a circumference of a circle:

<em>d</em> - <em>diameter</em>
<em />
We have <em>d = 4m</em>.
Substitute:

Use 3.14 for π:

Answer:
true
Step-by-step explanation:
English translation:
If the quality control manager wants to estimate the average life of lamps with 20 hours, with a confidence level of 95% and an error of 10% is assumed. What is the sample size?
Well a right triangle is made up of a 180 degree angle and take away 90 degrees because the right angle is already there so the answer is that PQR is a right triangle since the other two angles = 90 when added hope this helps i did alot of research:)