d = distance between the two point charges = 60 cm = 0.60 m
r = distance of the location of point "a" where the electric field is zero from charge 
between the two charges.
= magnitude of charge on one charge
= magnitude of charge on other charge
= 3
= Electric field by charge at point "a"
= Electric field by charge at point "a"
Electric field by charge at point "a" is given as
= k /r²
Electric field by charge at point "a" is given as
= k /(d-r)²
For the electric field to be zero at point "a"
=
k /(d-r)² = k /r²
/(d-r)² = 3 /r²
1/(0.60 - r)² = 3 /r²
r = 0.38 m
r = 38 cm
<span>Pollination is the process by which pollen is transferred to the female part of a plant. The stigma is the central part of the flower, that is supported by a style and is part of the female reproductive organ within plants. Its structure is optimised to promote pollination by having hairs, sticky surfaces and three-dimensional sculptures that capture and trap pollen.</span>
The answer is b
300,000 km
Is the number the whole thing equal to 1?
<span>Brownian
motion is the random movement of colloidal particles suspended in a fluid. It is
caused by random collisions of the molecules in the fluid medium. The particles
in the solution or colloids are in constant random movement. A colloid has
properties boundary to a homogenous and heterogeneous mixture. However in
Brownian movement, the larger the size of a particle, the lesser its motion and
the smaller the size of the particle, the higher is motion. Colloids in general
have larger particle size and therefore it Brownian motion is sluggish. The statement
is false.</span>
