Answer:There are total 118 elements in world as about marbale
Explanation:
Frequency is represented by f in the formula v=fπ. Where π is wavelength , f is frequency and v is velocity. Frequency is the number of waves passing per unit time.
They use information from other things that relate to that topic and then use that to do their research
Answer:
Protons are positively charged. When a nucleus emits an alpha particle, these changes happen: the mass number decreases by 4. the atomic number decreases by 2.
Explanation:
There are 2 significant figures. All numbers in a whole number are significant.
