What is the power required to lift a 340n weight to a height of 3.5 meters in 5s

Work (W) is defined as the force applied over a distance.
$W = F \times d$
Where:
$F = 340\ \text{N}$ (force/weight)
$d = 3.5\ \text{m}$ (distance/height)

$W = 340\ \text{N} \times 3.5\ \text{m}$
$W = 1190\ \text{J}$

Power (P) is the rate at which work is done, or work divided by time.
$P = \frac{W}{t}$
Where:
$W = 1190\ \text{J}$ (work done)
$t = 5\ \text{s}$ (time taken)

$P = \frac{1190\ \text{J}}{5\ \text{s}}$
$P = 238\ \text{W}$

The power required is 238\ W.