Find the correct statements:
A. In human pregnancy, the major organ systems are formed at the end of 12 weeks.
B. In human pregnancy, the major organ systems are formed at the end of 8 weeks.
C. In human pregnancy, heart is formed after one month of gestation.
D. In human pregnancy, limbs and digits develop by the end of second month.
E. In human pregnancy, the appearance of hair is usually observed in the fifth month.
Choose the correct answer from the options given below:
Total number of possible isomers (both structural as well as stereoisomers) of cyclic ethers of molecular formula $C_{4}H_{8}O$ is:
A full wave rectifier circuit with diodes (\(D_1\)) and (\(D_2\)) is shown in the figure. If input supply voltage \(V_{in} = 220 \sin(100 \pi t)\) volt, then at \(t = 15\) msec: