All the none-zero digits given should be included when written in scientific notation. But also any trailing zeros written after non-zero digits should also be included.

For example in 0.00900 the 900 is significant because the person who included the trailing zeros is saying look I measured this far and these zeros are significant.

5 0

3 years ago

Please help me this is so confusing to me.

Naddik [55]

Hi there! :)

$\large\boxed{A = 120^{o}}$

Find the central angle using a ratio in regards to angle and circumference.

The radius is 27 units, so use the following equation to calculate circumference:

C = 2rπ

Therefore:

C = 2(27)π = 54π

Since we have the total circumference, we can write the following proportion:

$\frac{x}{360} = \frac{18\pi}{54\pi}$

Cross multiply:

54πx = 6480π

Divide both sides by 54π to isolate for x:

x = 120°

8 0

3 years ago