Answer: 0.5
Explanation:
There are 13 hearts. The chance of drawing a heart in your first draw is 13/52, or in other words 1/4
There are 13 diamonds. The chance of drawing a diamond on your second draw is 13/52, or in other words, 1/4
The chance of drawing a heart, replacing it, drawing a diamond, are 1/4*1/4=1/2.