Characteristic blue eyes and blond hair?
Group 1 & Group 2 contains only metals
Hope this helps!
This is called the Mass Number of the isotope of the atom.
Isotopes are different forms of the same atom. They have the same number of protons but different number of neutrons.
Carbon-12 has mass number 12 as it has 6 protons and 6 neutrons.
Carbon-14 has mass number 14 as its has 6 protons and 8 neutrons.
Answer:
400 or 4x102 indicates only onesignificant figure. (To indicate that the trailing zeros are significant a decimal point must be added. 400. has threesignificant digits and is written as 4.00x102 in scientific notation.) Exact numbers have an infinite number of significant digits but they are generally not reported.