Yes, business management is the mundane dharma, and being a volunteer is Buddha dharma.
2
世间法都是相对待的。
The phenomena of the world come in pairs of opposites.
3
菩萨也厌离世间法,佛更是厌离世间的一切法,不生一切染污和执著。
Bodhisattvas detest worldly dharmas, and Buddhas detest worldly dharmas even more. They are not defiled by craving for them, and they are not attached to them.