For the second one it is physical
Answer: A force must cause an object to move along the same direction as the force.
Explanation:
Work is defined as displacement in the position of an object due to action of force. Mathematically the work done is a product of force and displacement of an object. The direction of the force applied and direction in which object is displaced is always same.

When work is done,a force must cause an object to move along the same direction as the force.
Mv^2 = const
<span>m ~ 1/v^2 </span>
<span>(4.5/10.1)^2 = 0.198 </span>
<span>20.2 * 0.198 = 4.0 g/mol (Helium)</span>
Answer:a) 0.1 mole. b) 4g. c) 2% d) 196 mL
Explanation: in 200mL , 0.1mole
mw NaOH = 40g/mol —> 4g in 0.1 mole
4g in 200mL so 2g in 100mL
density NaOH = 1g/mL so if 4g in 200 mL, 4mL , 196 mL water