Answer:
<h2>
503 cm²</h2>
Step-by-step explanation:
The surface area of the figure is sum of areas of two triangles and three ractangles:

I would think its D, but not totally sure
The 200 parents. It basically means the amount/number of the population you are testing. In this case it would be the 200 parents.
I think the best approach is assuming in percentage. if the cake= 100, then just add the 47 and 23. that would equal 70. then, subtract the 70 from the 100. that would be 30 as your final answer.
« 47+23+?=100 »
« 70+?=100 »
-70 -70
?=30
That would be 36 / 60 = 3/5 of an hour Answer