Question

click in the box with the blue arrow pointing to 1 yard on this line:
0
1 m
2 m
3 m
click in the box with the blue arrow pointing to 1 meter on this line:
0
1 ft
2 ft
3 ft
4 ft
5 ft
click in the box with the blue arrow pointing to 50 centimeters on this line:
0
1 m
2 m
3 m

Explanation:

Step1: Convert yard to meters

1 yard = 0.9144 m, so it is the box just before the 1m mark (top line, upper blue arrow).

Step2: Identify 1 meter in feet

1 m ≈ 3.2808 ft, so it is the box between 3ft and 4ft (middle line, third blue arrow from top).

Step3: Convert 50 cm to meters

50 cm = $\frac{50}{100}$ = 0.5 m, so it is the first box above the 1m mark (bottom line, topmost blue arrow).

Answer:

1. For 1 yard: The box just left of the 1m mark (top line, upper blue arrow)
2. For 1 meter: The box between 3ft and 4ft (middle line, third blue arrow)
3. For 50 centimeters: The box halfway between 0 and 1m (bottom line, top blue arrow)