Classify the following as slow and fast changes.
Formation of curd from milk

Explanation

To classify the formation of curd from milk as a slow or fast change, we can follow these steps:

### Step 1: Understand the Process
The formation of curd from milk involves a biological process where bacteria convert lactose (milk sugar) into lactic acid, which causes the milk to thicken and form curd.

### Step 2: Determine the Time Frame
This process does not happen instantly. It typically takes several hours for the milk to transform into curd. Generally, it takes about 6 to 8 hours for curd to form.

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