Answer:
I believe the answer is d, but im not quite sure
Step-by-step explanation:
She would have traveled 24 miles since from the house to the supermarket is 7 miles then from the supermarket to the municipal building is 5 miles then back 7 miles and then 5 miles. If you add all of that together then you will get 24 miles.
It depends on what is being referred to by "this."
The description of the activity is that 10 drops are added twice and two readings are taken. If you do *that* 4 times, then a total of 20*4 = 80 drops will have been added.
If the activity referred to by "this" is the pair of acts {add 10 drops, read the volume}, then four repetitions will have added 10*4 = 40 drops.
Probably the expected interpretation is that "this" is {add 10 drops, read}, so 40 drops is likely the expected answer.