Will mark Branliest for correct answers
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Answer:
1. 276040 = 300000
2.£200
3. 20000km
Step-by-step explanation:
According to some reaserch,
To round to a significant figure:
1. look at the first non-zero digit if rounding to one significant figure
2. look at the digit after the first non-zero digit if rounding to two significant figures
3.draw a vertical line after the place value digit that is required
4. look at the next digit
5.if it's 5 or more, increase the previous digit by one
6.if it's 4 or less, keep the previous digit the same
fill any spaces to the right of the line with zeros, stopping at the decimal point if there is one