If '9 About two-thirds of the production volume of our surveyed business units did their marker-making, spreading, and cutting in a single location.' is true, does it logically mean that 'The surveyed businesses worked in the timber industry.' also is?
9 About two-thirds of the production volume of our surveyed business units did their marker-making, spreading, and cutting in a single location.###The surveyed businesses worked in the timber industry.