Find the charge q(t) flowing through an device if the current is:(c) i(t)= 20 cos(10t + π/6)10^-6A, q(0)=2(10^-6)CMy problem in this question is the substitution.I know that u=10t+π\6 , and u'=10, but the u' doesn't equal to the 20 in front of the cos, how do I find the derivative that will equal the "20".

Two current-carrying wires are separated by a distance of d = 20 cm as shown in the figure below. The wire on the left carries a current of I1 = 4.23 A and the wire on the right carries a current of I2 = 2.16 A. What is magnitude of the magnetic field |B| at the midpoint (d/2) between the two wires shown in the figure below? Give your answer in units of micro Tesla ( µT) Image size: s ML Max I1 I2 d