A) All triangles add up to 180° so when given two angles, add those up and subtract them from 180° . That will give you the missing angle.
3-5) When you do A above, and receive the measurement of angle 1, it will also equal 2 and you can repeat A for missing angle 3
6-8) Find the missing angle next to 1, and then subtract that from 180°. That number is the answer for 1. 2 is 55 as its a complimentary (i think thats the right term) angle. Which means it is on the opposite side of an angle. I don't remember how to find 3 however, its been a few years since I've done triangles.
Well really it would have to depend on the flashlight. Is it an led bulb or a regular bulb?
1. Mean is the number you get when you add all these numbers and then divide by the number of numbers. So, (31 + 28 + 30 + 31 + 30) / 5 = 150 / 5 = 30
2. The median is the middle number in the list of numbers, so, the answer is 30 as well.
3. Mode is the number that appears most often, so here it is 30 and 31 because they both appear 2 times.
4. Range is the difference between the largest and smallest number, so 31 - 28 = 3.