Kindly help me to solve the following plzz....with proper Explanation.......

Here, in a) part  if  we multiply 8 × 125, we get, 1000 which ends with 0. So, we multiply them first.
b) part if we multiply 4 and 20, we get 80. It also ends with 0. Then, we multiply 80 and 25 and it gives 2000 which also ends with 0. So, we multiply them.
d) part if we multiply 5 and 20, we get 100 which ends with 0. So, we multiply them.

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Regards!