A ladder will be used to gain access to a rooftop and will extend a total of 16` from the ground to the top support. For the angle of the ladder to comply with OSHA standards, the base of the ladder shall be a minimum of ____ feet from the vertical wall.

A ladder will be used to gain access to a rooftop and will extend a total of 16` from the ground to the top support. For the angle of the ladder to comply with OSHA standards, the base of the ladder shall be a minimum of ____ feet from the vertical wall.