Answer:
Area of shaded region = 351.68 cm²
Step-by-step explanation:
Area of a circle = πr²
where r = radius = 3.14
Area of bigger circle = 3.14 × 11²
= 3.14 × 11 × 11
= 379.94cm²
Area of smaller circle = 3.14 * 3²
= 3.14 × 3 × 3
= 28.26cm²
Area of shaded region = Area of bigger circle - Area of smaller circle
= (379.94 - 28.26) cm²
= 351.68 cm²
If you're taking trig, the "sum and difference formulas for trig functions" are basic facts that you'll need to learn and commit to memory. I'd suggest you look up these formulas on the net. You will likely immediately find listings for the sine, cosine and tangent.
There are 60 minutes in one hour.
Divide 60 minutes by 10 minutes.
You get 6. That means you would need 6 recycled bottles to power a washing machine for one hour (that will be awesome if that were the case).
Have an awesome day! :)
To get the answer we can use proportion
40$ ------------- 100%
2$ ---------------- x
crossmultiply now
40x=2*100 /:40
x=200:40
x=5% - its the answer