The rate of healing, A′(t)(in square centimeters per day), for a certain type of abrasive skin wound is given approximately by the table.

t 0 1 23

A′(t) 0.91 0.83 0.76 0.69

t 4 5 6 7

A′(t) 0.62 0.58 0.48 0.44

Use left and right sums over five equal subintervals to approximate the area under the graph of A′(t) from t=0 to t=5.

The left sum, L5, is .

The right sum, R5, is .