Isotopes of the same element have different? ?

numbers of neutrons

Explanation: Isotopes are different versions of a particular element or different versions of a certain kind of atom.

Protons and electrons determine an atomic element's chemical characteristics. The neutrons are a different matter. They have no charge, but do have almost the same mass as a proton. Different isotopes of an atomic element contain different numbers of neutrons.

a: 45.9 meters

b: 4.29 seconds

step-by-step explanation:

a: h(t)=1/2(-9.8)(3)^2+0(3)+90

h(t)=-4.9(3)^2+90

h(t)=-44.1+90

h(t)=45.9 meters

b: 0=1/2(-9.8)(t^2)+0t+90

0=-4.9t^2+90

-90=-4.9t^2

18.37=t^2

t=4.29 seconds

in the second question, the numbers aren't exact, but they're a close approximation.

just did the assignment and the answer was #1 +2 n