A closed system is a system that is completely isolated from its environment. The physical universe, as we currently understand it, appears to be a closed system. An open system is a system that has flows of information, energy, and/or matter between the system and its environment, and which adapts to the exchange.
D makes the most sense, but you just have to put two and two together and go with your gut feeling, first cross out the answers that don't make sense (A didnt make sense) and go from there! I hope the little bit above me helped you answer or decide :) Good luck!
Thank you for posting
your question here at brainly. Feel free to ask more questions.
<span><span>The
best and most correct answer among the choices provided by the question is </span>B.-2.71 V.</span>
Mg2+(aq) + 2e- -> Mg(s) E=-2.37 V
Cu2+(aq) + 2e- -> Cu(s) E =+ 0.34 V
Since Cu is acting as the anode, the equation needs to be
reversed.
Cu(s) -> Cu2+(aq) + 2e- E =- 0.34 V
Ecell= -2.37 V+ (- 0.34 V) = -2.71 V
<span><span>
</span><span>Hope my answer would be a great help for you. </span> </span>
<span> </span>
1. Answer: A skydiver whose air resistance is equal to that of her weight.
A skydiver free falls under gravity but her rate of fall slows down due to drag -air resistance. when this air resistance becomes equal to her weight, the two get balanced and the body does not accelerate or decelerates.
2. Answer: Gravity
Contact forces are those which act when there is physical contact between two bodies. For example: normal force, tension and spring force.
Non-contact forces act between two bodies even when they are at a distance apart. For example: gravity, electric force, magnetic force etc.
3. Answer: The tendency of an object's motion to remain the same.
Inertia is a property of matter by virtue of which it tends to remain in its state of motion or rest. It does depend on mass of the object, more the mass, more is inertia. For example, cycle can be easily moved but we need real push hard for a car to move.
4. Answer: 254 N
The man pushes the box with 310 N force at an angle of 55 degrees to the horizontal.
we can write this in terms of horizontal (
)and vertical component (
).
Horizontal component: 
Vertical component: 
The vertical component would act towards the floor making the job more difficult to move the job.
Using formula:
I=(1/2)*M*(R^2+r^2)
<span>I=0.5*0.715kg*[(12.7cm)^2+(10.7cm)^2] </span>
<span>I=98.6 kg*cm^2</span>
Answer:
I want to say 10 seconds but im not 1000% sure