-3.8 is -3 8/10 which is -3 4/5 simplified
The first thing we need to do is find the rate of parts for 15 minutes.
So, we divide 114 parts per 6 minutes and get 19 parts per minute
Then we multiply this rate per minute by 15 minutes
The answer is 285
Attached Work Below:

A triangle can be drawn with exactly one acute angle is false (assuming the triangle is drawn on a 2-dimensional plane).
You would use B to find X
This should be the equation:
n + 4/3n + 5/3n = 90