(f) What do you mean by: (i) 1 J energy (ii) 1 W power​

Explanation:

Watts are defined as 1 Watt = 1 Joule per second (1W = 1 J/s)

which means that 1 kW = 1000 J/s. A Watt is the amount of energy (in Joules) that an electrical device (such as a light) is burning per second that it's running.

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2

i believe the answer would be:

d. violin, clarinet, french horn, and tuba