Answer:
A
Explanation:
The acceleration of an object is directly proportional to its net force.

Answer:
Option B
Explanation:
Magnification of Microscope is

Mo= Magnification of objective lens and
Me= magnification of the eyepiece.
Both magnifications( of objective and eyepiece) are inversely proportional to the focal length.
Magnification,

when the focal length is less magnification will be high and when the magnification is the low focal length of the microscope will be more.
Thus. Magnification will increase by decreasing the focal length.
The correct answer is Option B i.e. using shorter focal length
Scientific knowledge is based upon observation, and it is supplemented by experimentation.<span> Scientific research follows the scientific method, a four-step process that guides scientists in the accumulation of knowledge.</span>
Ptotal=Ptotal —> m1v1+m2v2=m1v1’+m2v2’ —> (1kg)(2m/s)+(1kg)(0m/s)=(1kg)(-1m/s)+(1kg)(v2’) —> v2’=3m/s
answer: v=3m/s