Answer: A hypothesis is generally based upon either someone else's observation or on previous studies.
Explanation: They just keep testing it to make sure it's <em>always </em>true.
Answer: 
is missing
Explanation:
In a nuclear reaction, the total mass and total atomic number remains the same.
For the given reaction:
To calculate A:
Total mass on reactant side = total mass on product side
4 + 9 = 12 + A
A = 1
To calculate Z:
Total atomic number on reactant side = total atomic number on product side
2 + 4 = 6 + Z
Z = 0
Hence, missing is .
Solute is something that is being dissolved { ex : sugar , salt}
Solvent is something that has ability to dissolve things { ex : water}
False because the solvent is present in larger amounts...
Answer:
The intercostal muscles also stabilize the chest wall; in full inspiration they contract to prevent the intercostal spaces being sucked inwards by the negative intrathoracic pressure generated by contraction of the diaphragm.
Explanation:
Hope this helps! Brainliest is always appreciated :)
