Answer:
42
Explanation:
Write 2% as 
2
100
Since, finding the fraction of a number is same as multiplying the fraction with the number, we have
2
100
 of 2100 = 
2
100
 × 2100
Therefore, the answer is 42
If you are using a calculator, simply enter 2÷100×2100 which will give you 42 as the answer.