At any given time, a 4-acre field contains an average of 200 kg dry weight of mallow plants. For these calculations, assume that the food chain shown below is isolated and that there are no other predators or sources of food involved. mallow plant > painted lady butterfly > phoebe > fox

Assume that the dry weight of each animal is on average as indicated below:
painted lady butterfly: 0.1 g
phoebe: 4 g
fox: 1 kg

Assuming that 10% of the biomass, as measured in dry weight, is transferred from one trophic level to the next higher level, calculate how many foxes the field could support at any given time. Show your work and include in your calculations how many phoebes and painted lady butterflies the field could support.