Answer: They should use 7 numeral spaces.
Step-by-step explanation:
It is given that agency needs to make 1,000,000 tags.
Since 1,000,000 is a 7 digit number.
hence, the number of numeral spaces should be equal to the number of digits as 1,000,000.
Therefore, if we use 10 digits and the condition that there should be no blank spaces then the number of numeral spaces they use is equals to 7.