R2=XL means that I2 lags behind U2 (voltage on C) by 90 degrees, and I 1 leads U2 by 90 degrees, and I=I 1+I2= 10 A, which is in phase with U2 (the phasor diagram is clear at a glance, and the inductive and capacitive currents cancel each other out and resonate in parallel). So it is also in phase with U, U = I * R+U2, U2 = U-I * R = 200-10 * 5 =150, XC =150//kloc-0 =/kloc-0.