Given:
The diameter of cloud-water droplet is

The diameter of pinhead is 0.001.
Explanation:
Divide the dimater of cloud-water droplet by dimater of pinhead to determine the times as great is the diameter of a pinhead as the diameter of a cloud-water droplet .

So diameter of a pin-head is 100 times the diameter of water-droplet.
Answer:
You dind't include the answer choices but it should look something like

Answer
a. The backpack is $4.50
b. The sweatshirt is $2.70
Step-by-step explanation:
a. 30 x 0.15 = 4.50 (The 0.15 is from the price you are actually paying for the item. Because the item is 85% off, you are paying for 15% of the usual price. 15% as a decimal is 0.15 so you multiply that to the original price to find the amount u will pay.)
b. 18 x 0.15 = 2.70
Answer: Answer to be MAY be 18, I don't know. Just a guess.
Step-by-step explanation
Aww... I have a dog named Tilly, *Ahem* It would take 36 seconds. Hope this helpz...