To draw ∆ABC with the given measurements and the perpendicular from B to AC, follow these steps:

1. Start by drawing a straight line segment AB of length 5.2 cm.
2. At point B, draw a line segment BC at an angle of 100° to AB. The length of BC should be 5.2 cm.
3. At point B, draw another line segment BD perpendicular to AC. This line segment will intersect AC at point D.
4. To find point C, draw an arc with center B and radius 5.2 cm. This arc should intersect line segment BC at point C.
5. Finally, draw line segment AC to complete the triangle ∆ABC.

Your final drawing should have ∆ABC with angle BC measuring 5.2 cm, angle B measuring 100°, angle A measuring 60°, and a perpendicular line segment BD from B to AC.