WAEC - Economics (2014 - No. 6)
A normal supply curve has a positive slope which indicates that
sellers are willing to sell more at a lower price
sellers are indifferent to prices
sellers are willing to sell more at a higher price
there is always a fixed supply
Explication
A supply curve will normally slope upwards (positive) because sellers like it when they're selling at higher prices than lower ones. So they're more willing to sell at higher prices than lower ones.