For each of the following alternating quantities, determine
(a) the amplitude and r.m.s. value, and
(b) the frequency and period.
(i) e 250 sin 50πt volt
(ii) i 75 sin 628.3t milliamp
(iii) ? = 20 sin 100πt milliweber
(iv) v = 6.8 sin (9424.8t+?) volt.