A student weighing 700 n climbs at constant speed to the top of an 8 m vertical rope in 10 s. what is the average power expended by the student to overcome gravity?

560 watts.

Power is measured in watts which is joules per second. 1 joule is required to lift one newton one metre. Total energy used is therefore 700 x 8 = 5,600 joules. Total power is the number of joules used divided by the time in seconds 5,600/10 = 560w