The question is 6 please help

none of the answers are correct

Explanation:

Lithium = 3

Berillium = 4

Boron = 5

Carbon = 6

Mechanical energy = 429.984J

Explanation:

Given the following data;

Mass = 7.2kg

Velocity = 2.4m/s

Height = 5.8m

To find the mechanical energy;

Mechanical energy = kinetic energy + potential energy

First of all, we would determine the values of K.E and G.P.E

K.E = ½mv²

K.E = ½*7.2*2.4²

K.E = 3.6*5.76

K.E = 20.736 J

P.E = mgh

We know that acceleration due to gravity is equal to 9.8m/s²

P.E = 7.2*9.8*5.8

P.E = 409.248

Substituting the values into eqn 1, we have;

Mechanical energy = 20.736 + 409.248

Mechanical energy = 429.984J