Answer: 4
Step-by-step explanation:
To find the significant digits we have few methods.
METHOD 1--Count from left to right
A number that has a decimal point, count digits from the first number from the left that isn't zero.
METHOD 2--Count from right to left
A number that doesn't have a decimal point, count digits from the first number from the right that isn't zero.
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It is obvious that 507.2 has a decimal point, so we count from left which we will start with 5.
5, 0, 7, 2
There are 4 digits.
Hope this helps!! :)
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