The base of a straight or extension ladder should be set away from the wall at a ratio of __ from the top. 4:1 2:1 3:1 1:4

The correct answer is $4:1$.<br /><br />When setting up a straight or extension ladder, the base should be set away from the wall at a ratio of $4:1$ from the top. This means that for every 4 units of height from the top of the ladder to the landing surface, the base should be 1 unit away from the wall.<br /><br />This ratio is recommended to ensure stability and safety when using the ladder. It provides a sufficient distance between the ladder and the wall to prevent the ladder from slipping or tipping over while in use.