The types of radiation are Alpha, Beta and gamma radiation
Alpha radiation: is a radiation of particles like He elements. It is very heavy radiation. it can be stopped by a sheet of a paper.
Beta radiation: is a radiation of particles like as the electrons, with the same mass and positive or negative charge. It can be stopped by an aluminium sheet
Gamma radiation: is an electromagnetic radiation with out really mass, moves in the speed of the light and has very high energy, high frequency and very short wavelengths. It can be stopped only by a block of concrete, lead, or other heavy shielding.
Thus, the radiation has the lowest penetrating ability is <u>Alpha radiation (particles)</u>
Answer:
<em>About four million tons of </em><em><u>matter</u></em><em> are converted to energy in the Sun’s core every second</em>
Explanation:
<u>The Sun
</u>
It's estimated that The Sun fuses near 600 million tons 
of hydrogen into helium every second. As a result, 4 million tons of matter are converted to energy every second according to Einstein's equation 
Explanation: The first one
Source: it literally has fusion in the name
I believe that since Kepler focused his studies the rotation of the planets, and the stars, that he is the one who developed the law, which is called the first law of planetary motion.
