The equation for calculating the work when an upward force is applied to the item is
Work = mass×Gravity×height. Value of gravity = 9.8 ms^2
Substitute the values—
Work = 6.0 × 9.8 × 10.00 = 588 joules which can be written as 590 joules with correct no of significant figures.
Remember, the unit of work is joules, which is same as of energy because work is change in energy.