Which is an example of a heterogeneous mixture? Coffee, soil, gelatin or air

Soil. A heterogeneous mixture is not consistent throughout. The particles in air, coffee, and gelatin are dispersed evenly throughout the mixture. Soil is a mix of different objects. If you take a samples of soil from the same area you will find different objects in the soil. Even if you did find the same types of objects in the soil, they would not be exactly the same shape or size.