Final answer:
Rollerblading is easier on concrete due to the smooth, hard surface that provides minimal friction. Grass causes more resistance, making it harder for rollerblade wheels to move.
Step-by-step explanation:
It would be easier to rollerblade on concrete rather than on grass. This is because concrete provides a smooth and hard surface that offers minimal friction and resistance, allowing the wheels of the rollerblades to roll freely and smoothly. On the other hand, grass has a softer and uneven surface which can cause greater friction and resistance, making it more difficult for the wheels to move. Additionally, the design of rollerblade wheels is optimized for hard surfaces like concrete, not soft or uneven terrain like grass.