When the antibiotic penicillin was first introduced, it was immediately effective in combating
staphylococcus bacterial infections. After a number
of years, there were outbreaks of staphylococcal
infections that did not respond to treatment with
penicillin. The best explanation for this situation
is that
A. members of the original population of
bacteria that were penicillin resistant survived
and reproduced, creating a more resistant
population
B. the bacteria that survived exposure to
penicillin learned to avoid it
c. the bacteria that caused the new outbreaks
were from populations that had never been
exposed to penicillin
D. during each generation, the bacteria modified
their own DNA to increase their ability to
resist penicillin and passed this ability on to
their descendants

How does decreasing the gas volume affect the pressure of a gas?

Plz me ! 1 which of earths spheres contains most of its mass? a atmosphere b hydrosphere c geosphere* d biosphere 2 erosion and weathering are examples of which types of forces? a constructive forces b destructive forces* c gravitational forces d inertia-related forces 3 which of the following statements about earths atmosphere is true? a earths atmosphere contains 78% water vapor which is essentail to life b earths atmosphere contains 21% oxygen c earths atmosphere contains carbon dioxide which all life forms require d earths atmosphere allows radiation from the sun to pass through it and warm earths surface* 4 the strenght of the force of gravity between two objects is determined by which of the following factors? select all that apply a the messes of the objects* b the distance between the objects* c the volumes of the objects d the surface area of the objects 5 earth and moon are kept in there respective orbits due to the influence of a inertia b gravity c gravity and inertia* d neither gravity or inertia if you answer all questions right i will give

Reduction is a reaction which results in a in electrons and a in positive charge of the atom or ion 1) a- loss 1) b- gain 2) a-increase 2) b-decrease