A lead pencil consists of a cylinder of wood with a solid cylinder of graphite filled into it. The diameter of the pencil is 7mm, the diameter of the graphite is 1mm and the length of the pencil is 10cm. Calculate the weight of the whole pencil, if the specific gravity of the wood is 0.7 gm/cm3 and that of the graphite is 2.1 gm/cm3.

How do you find the Maclaurin series for tanx?

Why is Axiom 5, in the list of Euclid’s axioms, considered a ‘universal truth’? (Note that the equation is not about the fifth postulate.)

The smallest composite number is ______.

(a) 2

(b) 4

(c) 1

(d) None of these

Find the arithmetic mean of the first ten odd natural numbers.

A boat goes 24 km upstream and 28 km downstream in 6 hours. It goes 30 km upstream and 21 km downstream in 6 hours and 30 minutes. The speed of the boat in still water is

A. 10 km/hr

B. 4 km/hr

C. 14 km/hr

D. 6 km/hr