Hello, could you please help me with these physics questions? Thank you so much!

Problem 3 [Full credit 5]: A boy reaches out of a window and tosses a ball straight up with a speed of 10 m/s. The ball is 20 rn above the ground as he releases it. Use conservation of energy to nd a) The ball's maximum height above the ground. [ credit 1] b) The ball's speed as it passes the window on its way down. [ credit 1] c) The speed of impact on the ground. [ credit 1] d) A 72 kg bike racer climbs a 1200mlong section of road that has a slope of 43. By how much does his gravitational potential energy change during this climb? [ Hint: What is the height?] [ credit 2] Problem 4: A ball of mass m oscillates on a spring with spring constant k = 200 N/rn. The ball's position is x = (0.350 m) cos (15.0 t), with t measured in seconds. [Hint: The general expression for the displacement is 3' =AS 60'- [Full credit: 10] Compare these two equations to determine (a) Amplitude of the ball's motion, [ credit 2] (b) Frequency of the ball's motion, [ credit 2] (c) The value of the mass m, [ credit 2] (c) Total mechanical energy of the oscillator? [ credit 2] (e) The hall's maximum speed? [ credit 2] Problem 5: Electrostatic force [Full credit: 10] 1.0 nC -1.0 nC 4.0 nC A+ B (+ 1.0 cm 1.0 cm a) In the above figure, Charge A experiences an electric force BonA due to charge B and an electric force conA due to charge C. Using coulomb's law, calculate the magnitude and direction of these forces. [Hint: What is the direction of electrostatic force acting between positive-positive, positive-negative, and negative-negative charges)? [ credit 4] b) What is the magnitude and direction of net electric force on charge A? [ credit 2] The net force on A is c) What are the magnitudes of the charges qa qB qc qn to qE ? [ credit 2] Glass ball missing 3 Proton Electron 17 protons 1,000,000 protons electrons 19 electrons 1,000,000 electrons O A B D d) Calculate the repulsive force exerted by charges 1 and 2 on each other, where qi = 4q2. [ Hint: Coulomb's law] [ credit 2] N