Answer:
(2P + G) ft/min
Step-by-step explanation:
   P = speed of panda
P + G = speed of giraffe
rate of approach = speed of panda + speed of giraffe
              =       P        +      P + G
              = 2P + G
The panda and the giraffe are approaching each other at a rate
of (2P + G) ft/min.