A
.
Just
under
____________________
%
of
the
word's
population
,
about
____________________
billion
people
,
cook
indoors
using
____________________
or
other
elementary
techniques
.
____________________
cookstoves
,
lead
to
____________________
kitchens
and
smoky
lungs
.
____________________
,
lung
cancer
,
heart
disease
,
and
other
____________________
caused
by
indoor
air
pollution
kill
____________________
million
people
every
year
,
according
to
the
World
Health
Organization
.
B
.
In
2010
,
the
____________________
Alliance
for
clean
Cookstoves
replace
traditional
cookstoves
with
"
____________________
cookstoves
"
.
C
.
Clean
cookstoves
reduced
____________________
emissions
,
which
could
lessen
the
effects
of
____________________
____________________
.
They
might
require
less
____________________
to
be
burned
.
D
.
Based
on
a
Harvard
study
,
clean
cookstoves
release
more
____________________
into
the
air
.
They
are
also
____________________
and
are
not
often
used
.