Answer:
I think it is C.
Step-by-step explanation:
Have a good day. :-)
The unknown digit is 7 because 6.471 is greater than 6.470 and less than 6.48.
Answer:
3.456E + 14= 
Step-by-step explanation:
The river discharges
cubic feet of water into the Pacific Ocean each second.
There are 86,400 seconds in one day.
Amount of water discharges each day

Since this differs from what you have, I will explain the scientific notation.
3.456E + 14 simply means 
The options are not well laid out but you can pick the appropriate option.
5/9 = .55555555555 yards traveled per hop
15/9 = 1.6666667 feet per hop
Since both 4 and 6 are divisible by 2, it becomes 2/3<span />