D.DDT was used in WWII to control malaria and typhus.<span>
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Animals peeing and pooping in water which pollutes it
Answer:

Explanation:
We have series and parallel combination of two resisters
and
.
Series combination is
and Parallel is
Now dividing series equivalent resistance by parallel resistance gives us
.
Note! series Combination is simply superposition of two elements (resisters in this case ) in a circuit.
Answer:
w = vR/3
Explanation:
The centre of mass of the loop to bullet system is given by D / 4 from centre of loop, which is equivalent to R / 2 from its centre.
From the principle of conservation of linear momentum
, we have
m*v = 2*m* Vcm
Where v = velocity of bullet, Vcm = velocity of wood
Hence, we have
Vcm = v2
Also, from the conservation of angular momentum about the centre of mass.
M*V*(R/2) = Ic*w - equation (I)
where Ic = moment of inertia and w = angular velocity
Ic for a ring is given by
Ic of a bullet is given by
Hence, the moment of inertia of the system is given by the summation of the two moments of inertia Ic(ring) + Ic(bullet) which gives
Ic(system) = 
Substituting back into equation (I), we have

Hence, we obtain w =vR/3
w=v3R
Answer:
heterotrophs
Explanation:
According to the parameters established by biology, all living beings that require others to feed themselves are considered heterotrophs, that is, they are not able to produce their food within their organism but rather they must consume elements of nature already constituted as food, already synthesized by other organisms. Among the most prominent heterotrophs, all animals, bacteria and humans stand out.
The term heterotroph comes from the Greek, language in which the prefix hetero means different and trophies means food. In this way, the heterotroph is one that feeds on elements other than one, which takes elements from nature, from the surrounding space to feed. While autotrophic beings have the ability to synthesize inorganic elements such as light, water, carbon dioxide and convert them into food; Heterotrophic beings do not have that capacity, so they must consume plants (in the case that they are herbivores) or animals that have already consumed those plants (that is, in the case that they are carnivorous). In other words, animals and humans always need to feed on other living beings, they could never do so only from inorganic elements such as water.