The answer is :78 I think
true
Explanation:
this is because melting point and boiling point decreases down the group because they are held together by attractions between positive nuclei and delocalised electrons
Gravitational potential energy can be given by the equation
PE = mgh
where m is the mass,
g is the gravitational constant 9.81 or 10 depending on rounding
and h is the height
well weight is a force equiavlent to
W= m*g
so comparing that to the potential energy equation, divide the potential energy by the height and you will get weight in Newtons