I do not agree with the statement.
The "substance" can be a compound. It's "pure"
as long as there's nothing else in it but its name.
'Pure' water is 100% H₂O with nothing else in it.
'Pure' table salt is 100% NaCl with nothing else in it.
'Pure' carbon dioxide is 100% CO₂ with nothing else in it.
These example substances are all compounds, not elements.
The first answer should be correct if not then the second one
Answer:
b. calculate the constant force exerted on the pole vaulter due to the collision
mbgiclbxhkr and you can see the pole and you are not to be a great friend of the day and night sweets is my first day of your life and my friends is my friend