It ends with a 2, so it must be rounded down to 840.
840
It is already rounded to the nearest ten as 840
145
3.1416
The answer depends on the value of A.
270
60
It is then 740 when rounded to the nearest ten.
36,184 rounded to the nearest ten thousands place is 40,000.
That depends on the value of A.
2602 rounded to the nearest ten is 2600.