Answer and Explanation:
The computation is shown below:
The ac frequency in the United States is 60 Hz 
 The ac frequency in Europe is 50 Hz 
 So, 
Time for 25 spark in United stated is 25 ÷ 60 s 
 Time for 25 spark in Europe is 25 ÷ 50 s 
 Now 
Tape length in United States is
 = 0.5 × 9.8 × (25 ÷ 60)^2 
= 0.85 m 
= 85 cm 
And, 
Tape length in europe is 
= 0.5 × 9.8 × (25 ÷ 50)^2 
= 1.225 m 
= 122.5 cm 
So, As it can be seen that 
= 122.5 cm - 85 cm
= 37.5 cm
Europe has 37.5 cm more than in the United States