Im assuming the height is dropped so that it is the halfway point. this would then make the base 5cm, with a height of 12cm. if that is the case then the answer should be 13
Recall the inclusion/exclusion principle:

which means
Answer:
b and c
Step-by-step explanation: If you subtract 23 from 23/ 23-23=0 and 23-(-23)= 0. Hope this helps!