How many main types of muscles are there?

The polar equation $\cos \theta + 7 \sin \theta = \frac{1}{r}$ represents a

Genes that are involved in turning on or off the transcription of a set of structural genes are called

Which of the following uses $RNA$ as a template strand for $DNA$ synthesis?

The specific resistance (resistivity) of material $B$ is twice that of material $A$. The diameter of a circular wire made of $B$ is twice that of a wire made of $A$. If the resistances of both wires are equal,then the ratio of their lengths $l_B/l_A$ will be .......

An unbiased coin is tossed to get $2$ points for turning up a head and $1$ point for the tail. If three unbiased coins are tossed simultaneously,then the probability of getting a total of an odd number of points is