One
0.0816
140 This is because you take the first two numbers (in this case, they are 100 and 30) and these are the first two figures. You then round the 30 to a 40, because of the 8. This then gives you 140.
170 - (40%) = 102
40% =0.44/102/5
One
There are three. The 4, the 5 and the zero in between. The two last zeros serve only to properly space the decimal point which, in this number, is implied.
jku
0.0816
both 40 and 400 have one because there is no "." the 0.7000 has four SF because you know that the first three digits after the seven are exact while the last zero could be rounded. the concept is a little tough to get but once you do its pretty simple.
There are approximately 0.0255 miles in 41 meters.
20.8333
A, B and D.
140 This is because you take the first two numbers (in this case, they are 100 and 30) and these are the first two figures. You then round the 30 to a 40, because of the 8. This then gives you 140.
170 - (40%) = 102
The decimal part of 40 is 40 so the answer is 4080.
40% =0.44/102/5