Awave has a wavelength of 10mm and a frequency of 5 hertz what is the speed

Wavelength, frequency and speed can be related in the following equation
λf = v
where λ - wavelength (m)- the distance from one point of the wave to the same point on the next wave
           f - frequency of wave (Hz), Hz is number of waves per second 
           v - speed - ms⁻¹
substituting the values 
10 x 10⁻³ m x 5 s⁻¹ = 0.05 ms⁻¹
speed of the wave is distance the wave can travel within a second. 

Leaves specifically the gas exchange between plants and the environment. while plants undergo photosynthesis, they also partake in cellular respiration. respiration is the process that happens in the leaves of plants.