A worker applies a horizontal force to the top edge of a crate to get it to

Question:

A worker applies a horizontal force to the top edge of a crate to get it to tip forward (Fig. 8.36). If the create has a mass of 100 kg and is 1.6 m tall and 0.80 m in depth and width, what is the minimum force needed to make the crate start tipping? (Assume the center of mass of the crate is at its center and static friction great enough to prevent slipping.)