For light elements, what is the ratio of neutrons to protons that predicts a stable nucleas?
10: 5
2: 1
1: 1
1.5: 1

Answer is: the ratio of neutrons to protons is 1:1.

For example, nitrogen atom (N-14) has 7 protons (p⁺) and 7 neutrons (n°). The neutron–proton ratio (N/Z ratio or nuclear ratio) is 7 : 7 ( 1 : 1).

Another example, calcium atom (Ca-40) has 20 protons (p⁺) and 20 neutrons (n°). The neutron–proton ratio is 20 : 20 ( 1 : 1).

The neutron–proton ratio generally increases with increasing atomic number.

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )