1. A wave travels on a long rope of 390 cm and has an amplitude of 50 cm, a wavenumber 0.19 rad/m and period of 4.7 s. The rope is tied at one end to a wall and mike is pulling the other end with a force of 28 N. What is the mass (kg) of the rope?

2. Two charges q₁ = 5.2 C at point (0, 17) cm and q₂ = -7.2 C at point (9, 0) cm are on a xy coordinate system as shown in the figure. Determine the Electric Force magnitude (N) exerted on a third charge q_o= 4.6 C that is placed at point P (0,0).

Give answer to two places to the right of the decimal.