A "triangle" with the angles 0, 90, and 90 degrees cannot be considered a triangle since the two 90 degree angles make a right angle, and 0 degrees would mean a flat line. Rather it would resemble something like a straight U that is stretched sideways.
Answer:
12
Step-by-step explanation:
Listing the weeks he will attend each item
Class 4,8,12,16
Chess 2,4,6,8,10,12
Fencing 3,6,9,12
Starting today at week 0, he will attend all 3 again at week 12
The answer is .1
........