State the number of significant figures in 0.007 m².

The correct answer is One.

To determine the number of significant figures in the measurement $0.007{\text{ m}}^2$, we follow the standard rules for identifying significant digits:

1. Non-zero digits: All non-zero digits are always significant.
2. Leading zeros: Zeros that appear before the first non-zero digit are leading zeros. These zeros are not significant because they serve only as placeholders to indicate the position of the decimal point.

Applying these rules to the value $0.007$:
The zeros before the digit $7$ (the zero to the left of the decimal point and the two zeros to its right) are leading zeros and are not significant.
The only significant digit is the first non-zero number, which is $7$.

Therefore, there is only 1 significant figure in $0.007{\text{ m}}^2$.