Create the Lewis structure of NO2- using the following steps. NOTE: do only the step asked for in each part and then click Check–don't work ahead to solve the final structure. Step 1.
Count valence electrons in the molecule or ion. Do this by adding the periodic group numbers for each atom in the structure and adjusting for charge. Enter and Check.
Step 2.
Connect each pair of bonded atoms with a single bond by dragging bonds onto the molecule. Each bond decreases the number of available electrons by 2. Check.
Step 3.
Drag lone pairs of electrons to each terminal atom until each has an octet of electrons, or until all electrons are used. Check.
Step 4.
Place remaining electrons on the central atom. If the structure is already correct, or no electrons remain, press Check.
Step 5.
Examine the structure. If it is correct, press Check. If the central atom has fewer than eight valence electrons, introduce multiple bonds. (In this activity assume that only C, N, O, P, and S typically participate in multiple bonds.) Change a single bond to a multiple bond by deleting one or more lone pairs on a terminal atom and dragging a multiple bond between that atom and the central atom

The answer to your question really depends on three things: how much water you have, how cold it is to start out, and how cold the things around it are. water actually freezes when it gets to 32 degrees fahrenheit (0 degrees celsius), but the time it takes to get there may be different.  let's start with the first. if you take two glasses, and fill one with a tiny bit of water, and the other about halfway, then put them both in the freezer, the one with less water will freeze first (you can try this at home, but i recommend using plastic cups and not glass ones).  now let's move on to the second part. let's say you have two glasses, and you fill one with really cold water that has been in the refrigerator, and the other with really hot water from the sink. if you put both of them in the freezer, the one that started out colder will freeze first.  for the third part, let's imagine that you have two glasses with the same amount of water in them, and the water is at the same temperature. imagine putting one outside on a really really cold day in georgia, and having a friend in alaska put one outside on the same day. since it would be so much colder in alaska, the glass of water there would freeze before yours.  so, if you took a tiny bit of really cold water in a glass, and put it outside on a cold day in alaska, it would freeze a lot faster than a big glass of hot water outside on a cold day in georgia. 

The answer is 4 i don't know if its right let me see.