Answer:
maybe the 3rd stance if your not sure try to search in googel
1 mole of NH4NO3 requires absorption of 25.7 kJ/mol.
Therefore; 1 kJ of heat energy is absorbed by dissolving 1/25.7 moles of NH4NO3.
Hence; For an energy of 73.0 kJ to be absorbed the moles of NH4NO3 that dissolves will be;
= (1/25.7 × 73)
= 2.84 moles
Hence; 73 kJ is absorbed by dissolving 2.84 moles of NH4NO3.

We know, 1 m³ of space can hold 1000 l of the substance.
⇛ 1 m³ = 1000 l----(1)
And, 1 l is 1000 times more than 1 ml
⇛ 1 l = 1000 ml------(2)
So, From (1) and (2),
⇛ 1 m³ = 1000 × 1000 ml
⇛ 1m³ = 1000000 ml
We had to find,
⇛ 1.40 m³ = 1.40 × 1000000 ml
⇛ 1.40 m³ = 140/100 × 1000000 ml
⇛ 1.40 m³ = 1400000 ml
⇛ 1.40 m³ = 14,00,000 ml / 14 × 10⁵ ml / 1.4 × 10⁶ ml
☃️ <u>So</u><u>,</u><u> </u><u>1.40</u><u> </u><u>m</u><u>³</u><u> </u><u>=</u><u> </u><u>1</u><u>4</u><u> </u><u>×</u><u> </u><u>1</u><u>0</u><u>⁵</u><u> </u><u>m</u><u>l</u><u> </u><u>/</u><u> </u><u>1.4</u><u> </u><u>×</u><u> </u><u>10</u><u>⁶</u><u> </u><u>ml</u><u>.</u>
<u>━━━━━━━━━━━━━━━━━━━━</u>