Answer:
98 cm²
Step-by-step explanation:
The area of a circle is:
[tex]A=\pi r^2[/tex]
A semicircle is half a circle therefore the area of a semicircle would be:
[tex]A=\frac{1}{2}\pi r^2[/tex]
We can plug in the given values into the equation:
[tex]A=\frac{1}{2}*3.142*(7.9)^2\\A=\frac{1}{2}*3.142*62.41\\A=\frac{1}{2}*196.09222 \\A=98.04611[/tex]
We need to round to TWO sigfigs meaning...
[tex]A=98 \ cm^2[/tex]
Sigfig rules:
Nonzero numbers are significant
Trailing zeros are significant (only if there is a decimal point)
Any sandwiched zero is signification (Ex: 405 --> 3 sigfigs)
