How Do I Solve These Complex Newtonian Force Problems?

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Help needed in Bunch of Newton/Force Problems!

So we went over these questions in school,... and I was absent.. So my teacher expects me to self-teach myself. But I have trouble with these specific questions (out of 50 questions )...

Please show me steps

Question 1:
A mass of 25 kg is acted on by two forces: F1 is 15 N due east, and F2 is 10 N due north. The acceleration of the mass is

A. 0.72 m/s2, 56.3° north of east.
B. 0.20 m/s2, east.
C. 0.72 m/s2, 33.7° north of east.
D. 1.0 m/s2, 33.7° north of east.
E. 0.20 m/s2, 56.3° north of east.

Question 2:

An astronaut lands on an earthlike planet and drops a small lead ball with a mass of 76.5 g from top of her spaceship. The point of release is 18 m above the surface of the planet and the ball takes 2.5 s to reach the ground. The astronaut's mass on Earth is 68.5 kg. Her weight on the planet is

A. 69 N
B. 395 N
C. 670 N
D. 990 N
E. 1.02 kNQuestion 5:

A lamp with a mass 42.6 kg is hanging from wires as shown. The tension T1 in the Vertical wire is
A. 210 N
B. 417 N
C. 570 N
D. 360 N
E. 730 NQuestion 6:

A lamp with a mass M is suspended from the ceiling by two cords as shown. The ratio of the magnitude of the vertical component of the tension in T2 to that in T3 is

A. 1:1
B. 1:2
C. 2:3
D. 3:2
E. 3:1

Question 7:

A vertical rope is attached to an object that has a mass of 40.0 kg and is at rest. The tension in the rope needed to give the object an upward speed of 3.50 m/s in 0.700 s is

A. 592 N
B. 392 N
C. 200 N
D. 980 N
E. 729 NQuestion 8:

A 6 kg block sitting on a smooth table is connected to a free-hanging 2 kg mass by a stretchless, massless cord that passes over a small frictionless pulley. The acceleration of the two-block system is

A. g
B.(1/2)g
C. (1/3)g
D. (1/4)g
E. (2/3)g

Question 9:

A 15 kg block sitting on a smooth table is connected to a free-hanging 5 kg mass by a stretchless, massless cord that passes over a small frictionless pulley. The acceleration of the two-block system is

A. g
B. (1/2)g
C. (1/3)g
D. (1/4)g
E. zeroQuestion 10:

Two tug-of-war teams are pulling on the ends of a rope, each team with a force of 1000 N. If the rope does not move, the tension in the rope is

A. 2000 N
B. 500 N
C. 1000 N
D. zero
E. 2000 kg
 
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Question 1: What is the total force (as a vector?) What are its magnitude and direction?

Question 2: Try s = 1/2 g t^2 (and remember that formula!)

Question 5: Dissolve the gravitational force in the directions of the cables. The lamp does not accelerate, what does this tell you about the magnitude of T?

Question 6: Probably similar to the other ones, but I'd need to see the diagram.

Question 7: Use F = ma. What is the net force needed? How does this force relate to the tension T?

Questions 8, 9: draw force diagrams. How do the pulleys transfer gravitational force to the block (doubling, canceling, ...)?

Question 10: Draw a free body diagram for the rope.
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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