A50. g pendulum swinging back and forth has a speed of 3.0 m/s at a height of 0.30 m. determine the total mechanical energy of the pendulum. 370 j 220 j 0.22 j 0.37 j

The answer is D 0.37 J
convert 50 g to kg and you get .05 kg
the total mechanical energy is kinetic energy plus the potential energy. 
so Etotal=1/2mv^2+mgh
Etotal=1/2*(.05kg)*(3.0m/s)^2+(.05kg)*(9.8m/s^2)*(0.30m)
Etotal=0.37 J