C is the answer because there is no variable for X which without it would make a horizontal line.
Check the picture below.
the piecewise function, has two subfunctions or behaviours, one if x < 1, meaning less, not equals, but less than 1, so it doesn't include one, so it has a "hole" on that endpoint.
and the second behaviour of the piecewise is if x ⩾ 1, larger or equals than 1, so it includes 1, so it has a solid ball on that endpoint.
I don’t know what the question is? If you’re looking for the amount she paid, the answer is Php 1,205.00.
Php 3,655.00
- 2,450.00
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Php 1, 205.00