Answer:
Ideal mechanical advantage of the machine is 2
Explanation:
Ideal mechanical advantage of the machine is

here we have to consider the distance

Answer:
Matthias Schleidan
Explanation:
because Matthias Schleiden found that all plants are composed of cells, and communicated the finding to Schwann, who had found similar structures in the cells. Other researchers confirmed the similarity, as explained in his book, where he concluded, "All living things are composed of cells and cell products.
This became the cell theory.
I learn that in my old school.
Answer:
Because the gravitational attraction of the Sun hold them in motion around it
Explanation:
For an object travelling in a straight path at constant velocity, the net force acting on the object must be zero.
The planets in the Solar System, however, do not experience a zero net force: in fact, the Sun exerts a gravitational attraction on them, whose magnitude is given by

where
G is the gravitational constant
M is the mass of the Sun
m is the mass of the planet
r is the average distance between the Sun and the planet
Due to the presence of this force, the Sun makes the planets 'deviating' from their straight path, forcing them to following an elliptical path around the Sun.
Because the effective charge of the nucleus increase from left to eight due to the increasing number of protons.
The greater charge pulls the electrons closer to the nucleus, decreasing the radius.