How do engineers solve the problem of using the smallest possible amount of explosives A. Engineers drill a hole into the column to demolish it
B. Engineers test a number of explosives into a column
C. Engineers guess a amount that is exactly what they need
D. Engineers try to keep the cost down for explosives

I think its A see ian no if you goin get it right but try

Explanation:

Engineers test a number of explosives into a column

Explanation:

To figure out how much they need, engineers study the building plans and also do the test by picking up a column that is not holding the building up, they drill a hole and put right amount of explosive they think is right and set it off.

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