Step 1 :Calculate the probability for 7 clients who drop off their dogs 80% of the time: \(0.8^7 = 0.2097152\)
Step 2 :Calculate the probability for 3 clients who drop off their dogs 40% of the time: \(0.4^3 = 0.064\)
Step 3 :Multiply the probabilities for all 10 clients: \(0.2097152 * 0.064 = 0.0134217728\)
Step 4 :Round the answer to the nearest thousandth: \(0.013\)
Step 5 :\(\boxed{\text{Final Answer: Part A: 0.013, Part B: true}}\)